Classic Computer Magazine Archive COMPUTE! ISSUE 146 / NOVEMBER 1992 / PAGE S1

Compute's getting started with hard drives
by Mark Minasi, Tony Roberts, Dan Gookin

HOW HARD DRIVES WORK

What would happen if your Walkman cassette player married your stereo turntable?

The kids probably would be hard disks.

If you took the cover off a hard disk (don't!--you'll ruin your disk that way), you'd see one or more circular platters, something like small phonograph albums. Above them, there's a thin metal arm that sweeps in toward the center, or out toward the periphery of the disks. It actually resembles the tonearm used on phonographs.

Unlike a phonograph needle, this tonearm--called an actuator arm--never touches the platter while it's reading or writing. Each platter is coated with the same brownish, magnetic substance that covers cassette tape. (Generally, it's an alloy of iron, nickel, aluminum, and cobalt.) You won't find a phonograph needle at the end of the actuator arm, but a small magnetic head like the one that reads the cassettes in your Walkman. That small magnetic head is the disk head that you hear about when it causes damage via a head crash.

The disk head is kept off the platter by a very thin cushion of air 25 millionths of an inch thick. It resembles a hovercraft skimming above the surface of the ground. The disk's speed--56 miles per hour--would give most traffic cops pause.

Parking the head means moving the head to an area on the disk that doesn't contain data. You park the head before shutting the system down because removing the airspeed from the head could allow it to crash onto the platter below, potentially destroying data.

That will change in future drives. If the flying height of a drive head could be reduced, the head could pack more data onto a platter. A system that stores 100MB today might store four times that if the head could run right on top of the platter. Today, manufacturers are experimenting with sealed, fluid-filled drives that would do just that.

Drives also will fly faster in the future. Drives generally rotate at 3600 RPM, but drives that spin at the dizzying rate of 5400 RPM are beginning to appear. That means that a drive that delivers data at 1.5 megabytes per second today will be able to kick in the afterburners and blast data out at 2.3 megabytes per second!

What else could happen to change the drive world? Smaller drives. Just a few years ago, the smallest hard disks had platters that were 5 inches in diameter. Now, it's hard to find anything with a platter larger than 3 inches. Notebooks rely upon 2-inch drives. These drives will soon be available in capacities as great as 210MB. But it doesn't stop there. There are hard disks with platters just 1 7/8 inches in diameter: hard disks the size of a credit card.

For years, the experts have predicted that hard disks would be replaced by optical devices, flash RAM cards, and bubble memory, but since hard disks keep getting smaller, faster, cheaper, and more reliable, they should be around for awhile. Thimble-sized hard disks may soon grace the wristwatch-sized PCs we'll soon all wear.

HOW TO CHOOSE A HARD DRIVE

Now more than ever, it's a great time to upgrade your mass storage. Hard disks have gotten cheaper and cheaper. Prices are falling faster than the leaves from my hickory trees.

The first hard disk I ever purchased for my personal use was a 32MB Rodime. I bought it back in 1983, and paid $929 for it--a real deal at the time.

Nowadays, that $929 could buy me about 400 megabytes of disk storage space. Even if you don't want to spend that much--and most of you won't have to--there are a few things you should know before you plunk down your hardearned cash.

Shopping List

When you're buying a hard disk, consider speed, size, reliability, and cost. Just a few years ago, you'd also have to worry whether the hard disk used the IDE (Intelligent Drive Electronics) interface, and whether or not it parked itself on power-down. Today virtually all drives under 500MB use the IDE interface and are self-parking.

Although it shouldn't be their first question, most people usually want to know the price. A brief look at recent computer magazine ads shows that hard drive prices vary tremendously on a megabyte-per-megabyte basis. At 40MB, you'll pay $6.50 per megabyte. At 100MB, the price drops to $4.50 per megabyte. And, at 200MB and over, the price runs around $3.00 per megabyte.

Now, of course, there are exceptions. For example, the Fujitsu 330 MB IDE drive comes out to about $3.80 per megabyte, pricey for a drive in its size class, but there's a good reason for that--it's about fifty percent faster than the other drives in that class.

The best buy is a 200MB drive since that's the smallest drive that falls into the attractive three-bucks-permeg price range. At this writing, you can pick them up for between $550 and $650. Prices for 200MB drives have hovered in the mid-$500 range since June 1991, and that's a long time for prices to have remained stable.

The main reason prices have not fluctuated tremendously for more than a year is that the original big price decrease for the 200MB drives sparked a large demand, which resulted in shortages. But supplies are becoming more plentiful, so lower prices are probably just around the corner.

And does a big drive make sense? How big can you buy, anyway? The largest drive that you see mass-marketed is a 2.4GB drive--that's over two billion bytes--and there's even a 3 -inch drive from Seagate that stores 1.2GB. You don't need that much, but 200MB isn't too large by any means, even for home and small business use. I recently started using a 386SX notebook that I use primarily for Windows. After loading Windows, Designer, Excel, and Ami Pro, I'd burned up 65MB of disk space--and I didn't even install those programs with all of their options! Believe me, you'll have no trouble using 200MB with today's software.

Fast Track

Disk speeds are rated in terms of a disk's access time or seek time. Those aren't the same thing. Strictly speaking, the access time on most disk drives is equal to seek time plus 8.3 milli-seconds, though some ads aren't too clear about it. Ask to be sure which value is being advertised. Seek and access times are rated in milliseconds (thousandths of a second).

Don't even think about buying a hard disk with a seek time greater than 18 milliseconds. A few drives, like the Fujitsu I mentioned, run as fast as 12 milliseconds; better performance, but at a price.

There are actually two kinds of disk speed: seek time and data transfer rate. Seek time measures how quickly a disk can find a particular location and prepare to read the data at that location. Data transfer rate asks, "Now that you've found the data, how quickly can you read that data off the disk?"

Data transfer is rated in kilobytes per second and starts from about 500 KBps and goes up to about 1500 KBps. Compare those staggering numbers to those of my old $929 32MB drive, which had a 57-ms seek time and a 165-KBps transfer rate.

Next, consider reliability. Except for the occasional bad apple, drives are much more reliable than they were even a few years back. This extra reliability comes even though today's drives are of lower quality in some ways.

Improved technology accounts for this apparent paradox. Years ago, a drive could produce no more than one bad bit in a trillion in order to meet industry standards. Today, the standard has been relaxed to permit one bad bit in ten million. To compensate for the additional error tolerance, however, hard disks now have a built-in error detection and correction scheme that can correct errors of up to 70 bits in a row. Errors happen, but they're automatically found and fixed, resulting in robust and reliable drives.

Help with Hardware

When you buy a drive, you'll probably also need a drive controller. IDE drive controllers are quite inexpensive these days. I recently purchased a board that's a combination floppy controller, IDE hard disk controller, and interface with one parallel and two serial ports--for just $32.

When you purchase a drive, be sure to also buy the drive kit for a few more dollars. It contains the mounting hardware that you will need to install the drive. That can be particularly important because the hard disk that you buy will probably be in a 3 - inch container, and will probably have to fit into a standard 5 -inch drive slot. The mounting kit includes a bracket that fits in the big slot, but secures the smaller drive.

And be sure to jump up and down, scream, and insist on the documentation for the drive. If the vendor says, "Now, why would you need that?" Answer: "Because I already have an IDE drive, I want to install both drives, and I need to know how to set the jumpers to make this the second drive." (That'll shut 'em up.)

If you ever get around to installing a second IDE hard disk on your controller, you'll find that the process is simple except for one thing. You must set some jumpers on both hard disks to get them to cohabitate, and those jumpers vary in name and location from drive to drive.

Some refer to a first and second hard disk, others to a master and slave hard disk, others seem to use nonsensical acronyms to indicate first and second physical hard disks.

Since I've brought up the subject of second hard disks, I often get the question, "I have an old non-IDE hard disk. Can I keep it in my PC and use the new IDE drive?" The answer is possibly, but not probably. Your old hard disk uses a hard disk controller of a type known either as ST506, ESDI, or SCSI.

To keep the old hard disk, you will have to make two kinds of hard disk controllers work in the same PC without interfering with each other. One controller must be configured as a secondary controller. To do that, you'll need the documentation on the controller--it'll tell you which jumpers to move or switches to flip.

Fair warning, however. Many controllers don't have the option to play second fiddle, and many that claim to have the capability to be the secondary controller can't.

One more thought on controllers, particularly ones like the does-it-all controller I mentioned a while back. Insist on the documentation for the board as well, as those boards generally have about 20 jumpers that allow you to enable and disable all kinds of features. The documentation is essential. You'll be lost trying to change configurations without it.

HOW TO INSTALL A HARD DRIVE

Installing a hard drive is a sure way to boost the performance of your system.

If you do the installation yourself, it's also a way to learn something about the inner workings of your computer. Installing a drive isn't difficult, but there are a number of possible problems to consider.

If you buy your drive mail order, make sure a full set of instructions is included, and check out the vendor's policies on technical support before you place the hardware from a dealer, get a commitment for support and guidance--in case something doesn't fall into place.

If you're contemplating installing your own hard disk, I'm betting you're familiar with opening up and working inside your system. You've probably installed accessories such as a video board or an internal modem, so I won't go through the details of opening the system, installing cards, or connecting cables. Instead, let's focus on issues that will help you choose a drive and associated hardware that's appropriate for your system. Once you have all the right pieces and a set of instructions, installation is usually fairly straightforward.

One or Two Hard Drives

Chances are you already have a hard disk, but you're running out of room. Since most disk controllers support two hard drives, you figure that popping in a second drive won't be a problem. Maybe, maybe not, depending on exactly system. Changing technology may make it more practical to discard your current drive and install a new one rather than to simply add a second unit.

First, answer a few questions?

--Will your system's BIOS support the drive you intend to buy?

--Will your system's disk controller support the drive you intend to buy?

--Is there room in your system to install a hard drive?

If you run your system's setup program, you can access a list of drive types supported by the BIOS (Basic Input/Output System). The BIOS has to have an understanding of what your hard disk looks like (number of heads, cylinders, and sectors), so it can issue the proper instructions to access it.

If you have an older system, its drive table may not contain an entry for the large hard drive you're planning to buy. If this is the case, you'll need a BIOS upgrade before you can operate the new hard disk at its full capacity. The most recent BIOS releases allow for a user-defined drive type. It's sort of a fill-in-the-blanks form. Once you tell the BIOS your disk's specifications, it knows what to do.

Who's In Control?

Now, on to the controller issue. Practically speaking, you can only have one hard disk controller in your system, and all hard disks connected to that controller must use the same interface. The ST506 interface was prevalent on AT class systems. It supported MFM and RLL drives, which were once common, but are now difficult to find. These drives were typically small (less than 60 megabytes) and slow (greater than 25 milliseconds average access time). If you're buying a hard drive today, you probably want a capacity of at least 100MB and an access time of around 15 ms.

To get that kind of drive performance, you'll have to move up to a newer technology. Although other drive types exist--notably ESDI and SCSI--you're most likely to find yourself investigating IDE drives. ESDI and SCSI drives will provide you with maximum speed and capacity, but because of their expense, they tend to be used by only the most powerful of the power users.

In any case, none of these drives will work with your ST506 controller. You'll have to give up your old drive to embrace the new technology.

Now if you already have an IDE drive installed and want to add another to increase your capacity, you're in luck. Two IDE drives can be used in the same system.

Master and Slave

When two IDE drives are installed, one must be configured as the master and the other as the slave. These selections are made by covering certain pins on jumper blocks located on the drives. The drive documentation will show the proper settings. The master drive is the boot drive.

Be warned, however, that IDE drives of different manufacturers don't always get along. Sometimes this can be corrected by reversing the master-slave designations, but sometimes both drives want to be the master. Check with your vendor about return policies before you buy your hard drive. Make sure you can swap your drive for one from a different manufacturer if your original purchase doesn't work out.

IDE drives achieve some of their speed by including controller circuitry on the hard drive itself, eliminating the need for a separate controller. Nevertheless, IDE drives still require a host adapter card that occupies one slot in your system. The data cables from the hard drive and your floppy drives plug into the host adapter. Even though it's technically a host adapter, you'll often see it referred to as a controller.

If slots are getting scarce in your machine, consider buying an IDE host adapter that includes a serial, parallel, and game ports. The cost for the extra ports is negligible, and if you can free up a couple of slots in your machine, it's worth it.

Odds and Ends

In addition to your disk drive, you'll also need cables. Check your system's power supply to see whether there's a spare power cable available. If not, you may need to buy a Y-adapter, which splits an existing power cable and provides connections for two devices.

While you're looking at the power cables, check the size of the terminators. At one time all terminators were about an inch long, but as time marches on, so does miniaturization. Today's drives are getting smaller and many require connectors that are slightly less than one-half-inch in size. Adapters are available to convert from one size to the other; be sure to get one if you need it.

Also, be sure to pick up a data cable for your new drive.

Hard drives are available in 5-inch and 3 -inch sizes. Check your system to see which size bays are available. If you only have 3 -inch bays available, you'll be limited to 3 -inch drives. However, it's easy to put a 3 -inch drive into a 5 -inch bay with the proper hardware. You'll need a mounting tray which attaches to the drive; the tray is then secured into the drive bay.

Also, when inspecting your drive bays, check to see whether the sides of the bays are flat or whether there's a groove in the middle of each side. If the bays are grooved, you'll need mounting rails to install your drives. The plastic rails are attached to the sides of the drive. Then the rails slide into the grooves.

Drive vendors ordinarily supply you with all the necessary mounting hardware (often more than is necessary), but it never hurts to know what you need and to ask to make sure its included.

Hard disk prices have never been lower. Whether you do the installation yourself or have a dealer do it for you, now is a perfect time to expand your system storage.

10 TOP HARD DRIVE UTILITIES

Whether you're fixing the car, working with your computer, or gourmet cooking, the chore is always easier when you have the right tool for the job. Here's a list of software gadgets that will help you keep your hard drive running smoothly.

First, there are a couple of fully stocked tool boxes you might consider--PC Tools and the Norton Utilities. Both have long histories and loyal followings.

PC Tools 7.1 (Central PointSoftware, 15220 N.W. Greenbrier Parkway, Beaverton, Oregon 97006; 503-690-8090; $179) includes backup and disk optimization software as well as hard disk diagnostics and repair utilities.

Other features include a DOS shell and file manager, virus detection, data encryption, system information, a file finder, and a desktop manager.

Though most of the tools are DOS applications, the program includes some Windows support including full Windows versions of CP Backup and Undelete.

The Norton Utilities 6.0 (Symantec, Peter Norton Group, 10201 Torre Ave., Cupertino, California, 310-453-4600; $179) is a full set of data recovery, performance, and security utilities.

The program includes The Norton Disk Doctor as well as a cache, a disk optimizer, a disk editor, and tools to unerase and format.

The Norton Utilities also includes NDOS, a COMMAND.COM enhancement that adds options to DOS and increases the power of your batch files.

Vitamin Supplement

While The Norton Utilities and PC Tools each provides a wide range of software, PC users with nearly complete software collections may need only a specialty item. Here are some suggestions:

For hard disk backup, consider FastBack Plus 3.1 for DOS or FastBack Plus Windows (Fifth Generation Systems, 10049 N. Relger Road, Baton Rouge, Louisiana 70809; 504-291-7221; $189). FastBack offers automatic scheduling, tape support, flexible file selection options, and a snapshot feature that allows a disk to be restored to its exact state on any given day.

Central Point, which includes CP Backup in its PC Tools, also makes that program available in a standalone version for both DOS and Windows for $129. CP Backup 7.2 for Windows has been optimized to support the new features in Windows 3.1. Central Point's backup software permits unattended operation and supports QIC-40 and QIC-80 tape drives.

Symantec, too, produces well-respected backup software. The Norton Backup for DOS ($129) and The Norton Backup for Windows ($149) both provide a wide range of backup and restore options. Both programs offer flexible file-selection options and both permit automatically scheduled unattended backups. Backups are permitted to floppy, tape, or other hard disks.

Bigger Is Better

A sure way to get more out of your hard drive is to make it bigger. On-the-fly data compression is an idea that has started turning heads. Data compression permits you to store twice as much data in the same space--it's a hard disk upgrade without the hassle.

SuperStor 2.0 (AddStor, 3905 Bohannon Drive, Menlo Park, California; 800-732-3133; $139) is the data compression system that was incorporated into DR DOS 6.0. SuperStor works with both hard and floppy disks and is transparent to the user. Compressed floppy disks can be read on other systems even if SuperStor isn't running on those systems. The program includes a host of customization options.

SuperStor also includes a disk-defragmentation utility plus a recompression program that reshrinks compressed files to gain additional disk-space savings. Recompression runs behind the scenes when the CPU isn't busy.

Other SuperStor utilities permit the user to shrink or expand the size of the compressed volume. A utility called Analyze provides verification and repair functions similar to those of the DOS CHKDSK program.

Another data compression option is provided by Stacker 2.0 (Stac Electronics, 5993 Avenida Encinas, Carlsbad, California 92008; 619-431-7474; Stacker with AT/16 coprocessor, $249; Stacker 2.0 software only, $149.)

Stacker compresses both hard and removable disks to pack twice as much data on a single disk. The Stacker system is available as software only or with a coprocessor board which speeds operation and increases compression. The coprocessor version also uses slightly less memory than the software-only version.

Stacker 2.0 includes its own disk analysis and repair software as well as an optimizer that handles compressed drives.

If you want to coax more speed out of your hard disk, and your whole system for that matter, take a look at PC-Kwik Power Pak (PC-Kwik, 15100 SW Koll Parkway, Beaverton, Oregon 97006; 503-646-8267). This package features the Super PC-Kwik disk cache, which helps improve disk-access speed.

Built for Speed

A disk cache is a section of memory set aside to hold data as it's being read from or written to the disk. The cache software keeps track of frequently accessed data and keeps a copy of it in its memory area. The next time that data is requested, the cache can supply the data from memory rather than having to locate the data on the hard disk.

Programs that frequently access the disk, such as database programs or accounting software, really benefit from a disk cache.

In addition to Super PC-Kwik, the Power Pak includes utilities to enhance the speed of your screen, keyboard, and printing. You also get a copy of PC-Kwik Power Disk, a full-featured disk optimizing program.

Another program that helps keep hard disks humming is Spinrite II (Gibson Research, 22991 LaCadena, Laguna Hills, California, 92653; 714-830-8800; $89). Spinrite is designed to maintain the reliability of a hard disk by occasionally refreshing its low-level format. The big benefit is that this low-level formatting can be done without disturbing the data on the drive. If you have an older MFM or RLL drive that's becoming unreliable, a low-level format may be the answer to its problems.

Spinrite also identifies existing or developing disk flaws and prevents those areas of the disk from being used again. Any data stored in the area of the flaw is moved to a safe location.

Disks that employ sector translation--IDE, ESDI, SCSI--should not be low-level reformatted by the user. Although Spinrite won't low-level format these disks, the program's defect management features will function fully.

Finally, if you're looking for a way to manage everything that's stored on your hard disk, consider XTree Gold 2.5 (XTree, 4115 Broad Street, Building 1, San Luis Obispo, California 93401-7993; 805-541-0604; $149) or XTree for Windows ($49 through October 31, $99 thereafter).

XTree gives you a handful of file and disk management, compression, and viewing tools. With XTree you can move and hide directories, log multiple drives, and launch applications. XTree includes more than 50 file viewers, including viewers for many popular graphics formats. The DOS version also includes an undelete utility.

HOW TO LIVE WITH DIRECTORIES

I've seen some really junky hard drives in my day, littered with files. You may have one sitting on your desktop right now. You may be thinking "it works for me." Wrong. To get the most from your computer and its hard drive, you need a dose of organization. Similar files and programs should be kept in their own subdirectories. This allows you to find things easier, improves system performance, and makes you more productive.

Every disk has one main directory, the root directory. That directory is limited by DOS to holding only a few files, from 112 on a floppy disk to just over 500 on a hard disk. Even given that, I believe that no root directory should have more than five or six files in it. Everything else should be stuffed into proper subdirectories, and you shouldn't have more than a dozen subdirectories branching from the root. Any more, and you're not being organized.

Subdirectories are designed to handle the abundance of files that will eventually come to roost on your hard drive. Rather than haphazardly tossing things into the root directory, you can create a unique subdirectory and copy similar programs and files there. For further organization, you can create subdirectories within subdirectories four, five, six, or more levels deep. (The maximum limit is the size of the pathname, which can be no more than 63 characters long.)

Modern Architecture

All systems should have one basic subdirectory: a DOS subdirectory for DOS files and programs. Never copy all your DOS files to the root directory. Instead, create a DOS subdirectory and put your DOS programs there.

You should also have a general UTILITY or UTIL subdirectory for your utilities, a TEMP or JUNK subdirectory for temporary files, a BATCH directory for batch files, and so on. The directory names you use depend on what's on your system.

Modern PC software understands how subdirectories work; take advantage of this feature.

Whenever you install a new program, it will suggest its own subdirectory and create it on the disk for you. You can accept that suggestion, or select another directory or sub-subdirectory into which you can install the program.

For example, all my word processors can be in subdirectories off of the WP directory. Word processing documents are kept in other directories, each organized according to projects and clients.

Organization like this keeps the hard drive neat and tidy, but also lets you know more about a file than its limited 8-character name will tell you: It's easy to tell the difference between SCHEDULE.XLS in the /WORK/PERSONNEL directory and SCHEDULE.XLS in the /PRIVATE-/VACATION directory.

Clearing a Path

To make everything work, you need two more items--a search path and batch files. The search path is a list of subdirectories in which DOS can look for program files. Obviously, it makes sense to put the subdirectories you visit often on your path. But don't go over-board; it takes extra time for DOS to search for programs in each directory on your path.

The more directories you have, the longer it takes DOS to find a file, or to come back with a Bad command or file name error. Especially avoid subdirectories with only a single program in them.

The solution to the long path problem is to create batch files to run all your programs. Put a common BATCH directory on the path, along with other directories that contain more than one program to run, and you'll be set. Then continue to organize your hard drive using subdirectories.

When you add a new program, don't put its directory on the path--write a batch file for it and stick it in a BATCH directory on the path.

This whole organization concept falls under the category of hard disk management. You can find plenty of meaty books on the subject, and I suggest you look into one or more for good advice and plenty of examples. The end result will be a neatly organized and efficient computer.

Face it: Files on a hard drive are like dust bunnies under the couch; they accumulate faster than the national debt. With good organization and plenty of subdirectories, however, you'll always have a place to put your files.

HOW TO CHOOSE A TAPE BACKUP SYSTEM

If you're backing up your extra-large hard drives onto endless floppy disks, you've no doubt wondered about switching to a tape backup system. If your livelihood depends on your data, stop wondering and start shopping.

With the increasing interest in tape backup, tape drives are becoming more common and less costly. What makes tape backup drives so valuable is that if you have one, you'll actually use it.

Because a tape drive relieves you of the task of switching floppy disks, you can run your disk backups unattended. Simply start the program and step out to lunch.

There are several varieties of tape backup devices on the market, but the one that's most appropriate for individual computer users is the QIC-80 tape format. QIC-80 defines a standard method of encoding data on the tape so that a tape created on one QIC-80 device with QIC-80 software should be readable on another QIC-80 device. QIC-80 is an improvement of the older QIC-40 standard, packing twice the data on the same size tape. Although QIC-40 drives are still available and are a little less expensive than their larger cousins, I'd lean toward purchasing a QIC-80 drive. The convenience of the extra tape length is worth the extra cost.

A standard QIC-80 tape, which is about three-quarters the size of an audio cassette, holds 80 megabytes of data. Extended length tapes hold about 120 megabytes. If data compression is used during backup, you'll be able to pack as much as 250MB of data onto the extended length tape.

Tape costs range from about $25-$45 depending on whether they're purchased from a discounter or directly from the manufacturer. This may seem high, but when you can pack 250MB on one tape, the cost per megabyte of storage is considerably less than that of floppy disks.

Internal or External

Tape backup drives are available in either internal or external varieties. In general, the internal units are less expensive than external drives because with internal drives you don't need cases or external cables. External drives, however, have the advantage of being portable. You can use one drive to handle the backup chores on several computers.

Most of the tape backups in this class rely on the floppy drive interface for data transfer. Internal units typically hook directly into the floppy drive cable. External units require that an interface card be inserted into an empty slot in the computer. The data cable from the drive itself plugs into the interface card. Inside the system box, the floppy drive cable plugs into the interface board, and another cable links the interface board and the disk controller.

In most cases, if you plan to rotate an external unit among several computers, you'll need an interface card and internal cabling for each computer. You may also need an interface card if you plan to add an internal unit to a system that already includes two floppy drives.

Although most external drives require an internal interface card, several manufacturers offer another approach. The Micro Solutions Backpack tape drive connects to your computer's parallel port, providing both portability and flexibility. Colorado Memory Systems is offering a similar unit.

When you purchase a tape backup system, you'll receive backup software along with it, but in many cases, you'll be able to use your favorite backup software instead. The software that comes with the tape drives is usually adequate, but it rarely includes all the amenities found in separately purchased software.

If you already own backup software that you'd like to keep using, check its documentation to see which tape drives it recognizes, and shop for a tape drive system you know will work with your software.

Manufacturers of tape backup systems designed for personal or small network use include: Colorado Memory Systems, Everex Systems, Irwin Magnetic Systems, Maynard Electronics, and Micro Solutions.

54 ESSENTIAL HARD DRIVE TIPS

Here are my favorite tips for keeping you sane and your hard drive healthy. I use all of these tips on my own hard drives, and I suggest you follow them as well. The tips are listed in what I consider their order of importance.

Always Have the Latest Version of DOS

This applies to all software, but most importantly to DOS. You should always have the latest version of your disk operating system. With DOS 5.0, this is imperative. Not only does DOS 5.0 include important hard drive protection and recovery commands (MIRROR, UNDELETE, UNFORMAT), it's also able to handle large-capacity hard drives efficiently.

Upgrading DOS used to be a natural thing. Everyone knew the latest version offered better and more powerful utilities, the ability to address newer hardware, and fewer bugs than previous versions.

But DOS 4.0, which Microsoft gladly points out was produced completely by IBM, changed that. It was so buggy that it filled many of us with fear, uncertainty, and doubt about DOS 5.0. Rest assured, DOS 5.0 is solid. The next version of DOS will probably be solid as well, so upgrade!

1. A major concern with updating is software compatibility. A lot of people are stuck with DOS 2.1. Unfortunately, today's software requires at least DOS 3.3. Tomorrow's software--who knows? If it requires the latest version of DOS and you don't have it, you're stuck.

2. Updating your software isn't as necessary as updating DOS. I recommend ordering new software only if it offers features or fixes bugs that affect you. An exception is Windows, which is more an operating system than an application.

Backup Your Work

There's only one reason to backup: just in case. Nothing beats a safety copy of your data--even an old one. Even though it's logical, few users bother with it because backing up a hard drive is a pain--especially if you're using DOS's unfriendly BACKUP program.

Check out a third-party backup program. Fifth Generation Systems' FastBack is the granddaddy of them all, though PC Tools' Backup (CP Backup) and Symantec's Norton Backup also are fast and efficient. But here's the hottest tip of all: Buy a tape backup system. They're surprisingly inexpensive and they remove the disk-shuffling pain from the backup process.

1. Backup your entire hard drive at least once a month. Once a week is best.

2. Backup modified files--called an incremental backup--on a daily basis. This is done in DOS by using the BACKUP command's /M switch. If you don't do an incremental backup daily, do it weekly.

3. Perform a full backup of your work subdirectories every day.

4. Do a full backup before installing new hardware or moving your PC.

5. Never, under any circumstances, backup when you suspect a virus.

Use a Tape Backup System

For the price, nothing beats a tape backup. The backup unit itself is about half the cost of the hard drive it backs up, which isn't cheap, but you'll recover the expense in the time you save.

It isn't that tape backups are any faster than floppy backups (they usually aren't); it's that you can backup the hard drive without having to sit there, watch, disk swap, and repeat every few minutes. I start my tape backup just before I leave the office.

Tape backup is less expensive over the long run. With a tape backup system, you're archiving your hard drive's files to a cassette. The cassette alone costs less than an equivalent number of high-capacity floppy disks. And with the convenience of the tape backup, you can afford several cassettes that allow you to make backups more frequently.

1. For best results, get a tape backup system that can handle the full capacity of your hard drive. For example, if you have a 250M hard drive, get a system that can handle 250M cassettes.

2. Internal tape backup systems install just like extra floppy drives. The advantage of external units is that they can be moved around and used on several machines.

3. Make sure your backup software is compatible with the tape system you buy. Check with your software developer first.

Protect a Disk's Vital System Areas

Hard drives have both a physical and metal side. Both are safe when you backup, but the mental side occasionally may wander down to the lake for some fishing.

Tools, such as DOS's MIRROR command or similar commands from third-party companies, can help summon your drive back to work.

MIRROR creates an emergency copy of your disk's system area. This includes information about the disk, DOS's boot sector, and all the files and subdirectories in the root directory.

With an emergency copy of that information saved by MIRROR or a similar command, the chances for hard disk recovery after a disaster are increased.

1. To setup MIRROR with DOS, include the command in your AUTO-EXEC. BAT file. Here is the MIRROR command from my AUTOEXEC.BAT file: MIRROR C:D:E:

This protects drives C, D, and E. It's painless, quick, and takes only a few kilobytes of disk storage.

2. If anything bad ever happens, DOS's UNFORMAT command can recover your entire disk in a matter of seconds thanks to the MIRROR command. Recovery is possible without MIRROR, but slow and not as reliable.

3. MIRROR also can be used to activate deletion-tracking, which helps recover deleted files when you use the UNDELETE command.

Guard Against Viruses

The ugly reality of the 1990s is that computer viruses are real and nasty. Take steps to avoid them.

1. Avoid running any software from an unknown disk.

2. Never boot from an unknown disk, especially a game disk.

3. Buy only shrink-wrapped software or get shareware from a reputable discount house or computer club.

Sadly, DOS offers no built-in virus protection, but you can manually keep an eye on things. For example, ensure that the dates of important files don't suddenly change or that new, unknown files randomly appear.

4. You can use DOS's ATTRIB command to add read-only protection to a few vital files. Use it in this format: ATTRIB +R filename. For example, ATTRIB +R COMMAND.COM prevents files from modifying COMMAND.COM, a common technique used by viruses. Using the MIRROR command with its /PARTN option can also help fight hard-disk partition-table infection.

5. For real protection, you'll need a third-party virus scanner. Most of the major utility packages come with one, but virus removal requires a specific, anti-virus utility. Norton/Symantec offers one, as does Central Point Software. Fifth Generation Systems has a disk-protection utility called DiskLock, as well as an anti-virus program.

6. If you use your modem to download software, scan everything you download. Even if the system operator claims the files are clean, double check everything.

7. Be wary of games and beta software from curious sources--especially well-meaning friends. (If you really want a program, buy it outright.)

Curing a Full Hard Drive

When you run out of hard drive space, your options are limited. Delete files, move files onto floppy disks, or bite the plastic and buy a second or larger hard drive. Or you can be one of the booming disk-doubling software industry's converts.

The most popular disk-doubling package is Stacker. This ingenious utility doubles the capacity of your hard drive using on-the-fly compression that you'll never know is there. It works especially well with laptops. Stacker took my laptop's 40MB hard drive and painlessly converted it into an 80MB hard drive. Stacker, and programs like it, will do wonders.

1. If possible try not to compress drive C. Compress your other hard drives, but leave C alone. Or, if you have the space, create an empty compressed drive and copy files to it. The idea is to keep drive C clean so you can easily work with memory-management optimizing programs, as well as have a place for Windows' permanent swap file.

2. Stacker doesn't compress ZIP and some graphics and text files, so try to keep those files on an uncompressed disk.

3. The Stacker hardware option is really only necessary if you have an 8088, 80286, or slow 386 system. For faster 386 and beyond CPUs, the hardware option won't hurt, but it may not help that much.

4. You can also use Stacker to double the size of your RAM drives and floppy disks.

Use a RAM Drive for Temporary Storage

If you have memory to spare, a RAM drive can boost your hard drive's efficiency. You can use DOS's RAMDRIVE. SYS device driver, or capable third-party RAM drive software, to create one or more RAM drives. I use the following command in the CONFIG.SYS to create a 2MB RAM drive on my system: C:/RAMDRIVE.SYS 2048 512 256 /E

That drive becomes drive F on my PC. I copy batch files, utilities, and important DOS programs to that drive, then stick F:/ on DOS's search path. Access to all those files is slippery-quick, and since everything is in one directory, I keep only the F:/ on my path.

There are only two drawbacks to the RAM drive. The first is that it takes up RAM. If you're running Windows, that memory is best put to use by Windows. The same holds true for any program--if memory is tight, give it to your application and not a RAM drive. The second drawback is that the contents of a RAM drive disappear when you reset or turn off your PC.

Therefore, only put copies of files on the RAM drive. If you create anything new there--and you want to keep it--copy it to your hard drive as soon as you're able.

1. Create your RAM drive in extended or expanded memory, which must be specified using the proper command-line option or switch. I prefer extended memory because the RAM drive runs more efficiently. If you're using a memory manager such as QEMM-386 or 386MAX, then remember to reserve extended memory for use with the RAM drive.

2. RAM drives work best with disk-hungry programs, such as batch files. Databases also perform better when run from a RAM drive, but it's not an instant speed pill for everything. A good way to tell whether a program will run faster on a RAM drive is to keep an eye on your hard drive light. If it flickers often, then that program may work better on the RAM drive.

3. You may not have room to run everything on a RAM drive. Modern software requires several megabytes of storage space. If your program requires a megabyte of RAM drive storage space and memory is tight, consider using a disk cache instead.

4. RAM drives make excellent storage for temporary files. Both DOS and Windows use the TEMP environment variable, which you can set equal to the RAM drive's drive letter. When you do this, remember not to put a backslash after the drive lette; this upsets some Windows programs. To set my TEMP variable to the RAM drive F, I use SET TEMP=F:

5. While a RAM drive is OK for Windows' temporary files, you shouldn't direct Windows to put its swap file on a RAM drive. The swap file needs to be on a fast hard drive.

6. If you download programs from an online service, the RAM drive makes an excellent storage place. Exploding ZIP and other archive files on a RAM drive is lightning quick.

Use a Disk Cache

If memory is tight, a disk cache will outperfrom a RAM drive. A cache speeds up your entire hard disk, not just those programs copied to a RAM drive. DOS comes with disk-caching software, the SMARTDRV.SYS device driver. (In Windows 3.1, it's SMARTDRV.EXE.)

A disk cache is a special storage place in memory. All information read from disk is stored in the cache.

When your software wants to read that information again, the disk-cache software checks to see if the data is already in the cache.

If so, it's read from cache memory, which is much faster than reading from the disk again. Since most PCs access the same information over and over, the cache improves disk performance.

1. Caching under Windows is mandatory. The new SMARTDRV.EXE file installs painlessly into AUTOEXEC.BAT and automatically configures itself based on how much memory you have. Other popular disk caches include PC Kwik's PC Kwik, Norton's Ncache, and Golden Bow's Vcache.

2. Avoid caching your compressed drivers. Instead, cache the host drive only. Also, it's redundant to cache a RAM drive since it's already in memory. Use the switches and options on the disk-cache software to disable caching of those two types of drives.

3. If your cache has a write-ahead buffer, you should issue a command to write all information to disk before you turn off your PC or reset. For Windows' SMARTDRV.EXE, the command is SMARTDRV/C.

4. Some claim that DOS's FASTOPEN command is a disk cache. It's not. FASTOPEN is trouble. Avoid this command.

Optimize Your Hard Drive

Disk-optimizing software performs the miracle of defragmentation. By defragmenting a hard drive, you improve file access and performance.

The disk-optimizing software also can be used to improve your hard drive's interleave, revitalize your hard drive, and possibly recover and restore from hard drive misfortune. All the major hard disk utility packages come with a disk optimizer or defragmenter of sorts.

Fragmentation occurs when files are split into pieces to fill available space on a hard drive. DOS does this on purpose to make the best use of hard drive storage. DOS picks up the pieces and reassembles the file when you want to use it. The process works, but fragmented files take longer to load and save. Defragmentation software eliminates the fragmentation by laying each file end-to-end.

1. There are two types of defragmentation programs: fast and thorough. A fast program is ideal for daily use. A thorough defragmentation utility is methodical and slow. It reassembles every file on your disk, which can take up to two hours on a badly fragmented disk.

2. Don't defragment a hard drive until overall fragmentation reaches well above 10 percent.

3. Stacker has a special defragmentation program for its stacker drives: SDEFRAG. Run this program instead of a standard disk optimizer on your Stacker drives.

4. Do not use a disk cache--or especially the FASTOPEN command--when you run a disk optimizer or defragmentation utility. The best solution is to rename CONFIG.SYS and AUTOEXEC.BAT to something else, then reboot before you optimize. After optimizing, rename your configuration files back to their original names.

Organize Your Programs and Files Using Subdirectories

DOS is full of limitations and one of the biggies is that you can only have so many files in a disk's root directory. For a floppy disk, the number is 112. For most hard drives, 512 is the maximum.

To avoid filling a disk prematurely, create subdirectories. Unlike the root directory, subdirectories can hold an unlimited number of files. Still, don't go overboard. Instead, consider using the subdirectories as a form of hard drive organization: Put similar files into their own subdirectories. You can even put subdirectories into subdirectories to be very organized.

A hard drive organized into subdirectories becomes an efficient filing cabinet. For example, this article is saved in a subdirectory called COMPUTE, which is in a subdirectory called MAGAZINE, which is in my word processing directory. There's no doubt in my mind that files in that directory are for Compute magazine.

1. Subdirectories are named just like files, though they rarely have a filename extension. Name your subdirectories according to their contents. A MISC subdirectory is OK, but if it soon contains many similar files, create another subdirectory with an appropriate name: PRIVATE, POEMS, VACATION, GAMES, WORK, PROJECTS, 1992, and so on.

2. A quick way to see all the subdirectories is to use the DIR command as follows: DIR*.

Here only the files without extension are displayed, which is usually only the subdirectories. A more efficient way is to use the DIR command's /AD switch to display only subdirectories: DIR/AD

3. You can use the ATTRIB + H command to hide a subdirectory; however, anyone who knows the DIR /AH command can find it.

4. There's no DOS command to rename a subdirectory, but you can use the DOSSHELL program to rename a directory.

5. You can't delete a subdirectory unless completely empty, and you're not currently logged to it.

6. While there's no physical limit to the number of files you can have in a subdirectory, there is a practical limit. After about 500 files or so, access will be sluggish.

Use the PATH Command

To run a program quickly from anywhere on your hard drive, place its subdirectory on your search path. For example, to run programs in the DOS, UTIL, and WP subdirectories, you would set the following path: PATH = C:/DOS;C:/UTIL;C:/WP

1. Always specify a full pathname on the path--include the drive letter and subdirectories. Don't end a subdirectory name with a backslash.

2. Long paths slow your system. Limit your path to three or four subdirectories maximum. The best directories to put on the path are those that contain many files. A subdirectory that contains a single file--or no files--need not be on the path.

3. To run programs in subdirectories not on the path, create batch files. Place all those batch files in a central BATCH directory and place that directory on the path. And if you need to change the path, then do so in one of the batch files. (Remember to change the path back at the end of the batch file.)

4. Avoid the APPEND command, which works like a search path but for data files instead of programs. APPEND can be deadly because it will hunt out data files in other directories when you use the DEL *.* command.

Make or Break Network Connections in Batch Files

Logging into your network and connecting to network disk drives and printers is best done with batch files. Start by setting everything up in AUTOEXEC.BAT. Load the files necessary to run your network, log yourself into the network, then issue the NET or NET USE commands that connect your network disk drives and printers.

1. If you need to break a network connection, or reconnect at a later time, create individual batch files that do the job. For example, the following batch file is NEAR.BAT, which connects the user's PC to the printer next door:

@echo off rem connect to printer in

room 1037 use ltp1:

//msprint04/L141037a

The use ltp1: command is too long to commit to memory. The batch file makes it much easier to make the connection.

Manage Your Files Using Magellan

The best hard disk information tool is the disk navigator, Magellan, from Lotus. This program lets you work with files on disk and examine their contents in context. PC Tools lets you do the same thing with its viewer, as does the Norton Desk-top, but Magellan is much more logical and supports many file formats--including ZIP files, from which it can examine, update, and extract files.

1. The only disadvantage to Magellan is that it doesn't let you view two subdirectories at once. For that trick, you can turn to old standbys such as XTree, the Norton Commander, and the PC Shell and Directory Maintenance programs in PC Tools.

Buying a Hard Drive

The days of PCs being sold without hard drives are long over. If you don't already have a hard drive, buy one. If you have one, replace it or add a second hard drive since most PCs can handle two. In either case, buy the fastest, largest you can afford.

1. The hard disk you buy will require a controller card. Popular controller cards are compatible with the IDE, ESDI, and SCSI specifications. If you're buying a second hard drive, it must match your present controller. If you're starting out, I recommend the SCSI hard drives since they're more flexible and can handle more than two hard drives and other devices as well. Currently, the IDE drives appear to be the most popular with the masses.

2. You can install a hard drive by yourself. Physically, it's easy, requiring maybe a half hour of your time and skill with a screwdriver.

3. To prepare the new hard drive for use, follow these steps:

* Run DOS's FDISK utility to partition the drive. Divide the drive up into logical partitions if you like, or use it all as one huge drive.

* After FDISK partitions the drive, format it using DOS's Format command. If the disk is drive C, use Format's /S switch to make the drive bootable.

* After formatting, begin copying files to the drive. Remember to use subdirectories for organization. Keep as few files as possible in the root directory.

4. There's nothing wrong with buying a hard drive mail order. Check the refund policy on the drive and any guarantees. Also, make sure the vendor is friendly and offers after-sale support.