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Storage to Go
Removable media storage devices make saving and transporting data easier than ever. Here's what you need to know about capacities, technologies and prices to make the choice that's right for you.

-- by John Woram

Applications are hogs. They're so greedy for disk space, they're threatening to banish the dwarfish floppy disk drive to digital oblivion. As for tape, it's useful only for backups, and even then, it's as slow as ... well, as tape. That leaves the hard disk, whose high capacity and speed make it the storage medium of choice for just about everything. Now, if only it were portable, secure and practical as a backup medium.

Well, it is. The current assortment of removable-media devices combines the speed and capacity of a hard drive with the portability of a floppy. And when even that gigabyte hard drive starts to get cramped, removable media becomes an attractive alternative to installing yet another hard disk that's likely to get just as crowded over time. With a removable disk, you just pop another one in when you run out of space.

Then there's security. As long as your data resides in your system, someone can surely find a way to get at it. But if the data is on a cartridge in your pocket, it's nearly impossible for unauthorized eyes to see it without attracting your undivided attention.

As for backups, a high-capacity removable-media device takes much of the drudgery out of the task. Just open a DOS box (Sorry!) and use the XCOPY32 utility to copy the contents of an entire drive or selected directories to a removable-media disk. Because this backup disk is just another drive, you can access its contents without going through the usual restore procedure.

Finally, if you don't mind taking the easy way out, use your removable-media device as a boot drive. Install Win95 on one disk and your other operating systems on other disks. Or if your existing boot drive C: partition is configured for FAT32, use a conventional (FAT16) boot floppy to run Windows 3.x from the removable-media drive.

With all these capabilities, sales of removable-media drives are spinning into high gear, and the product array is dizzying. We'll take a look at four types of drive technologies, comparing everything from media capacity to cost per megabyte (derived by dividing the media cost by its formatted capacity). We'll also tell you how each of the eight drives we looked at stacked up in our Wintune 97 tests.

The four technologies we examined were magnetic media, phase-change rewritable, magneto-optical (MO) and floptical. We chose a mix of new and established products for our tests. Many are current residents of our WinList. Falling into the magnetic-media category were the Avatar Shark 250, the Iomega Jaz and Zip drives, and the SyQuest SyJet 1.5GB. In the phase-change rewritable category, we looked at Micro Solutions' backpack; in magneto-optical, we tested the Olympus SYS.230 and the Fujitsu DynaMO 640. And finally, in the floptical category, we looked at O.R. Technology's a:drive.

Are these drives SCSI or parallel? The short answer is yes-that is, as far as Windows 95 is concerned. After we installed the parallel port Micro Solutions backpack pd/cd and Avatar Shark 250 systems, Device Manager reported two new SCSI controllers on our system. It identified them as Micro Solutions backpack and Avatar Shark 250 drivers. Win95 provides SCSI emulation for such devices, which accounts for their presence in the Device Manager window. As for the others, they're all SCSI drives, with the exception of the a:drive, which is an IDE device.

We used our Wintune 97 benchmarks to test the speeds of all eight drives. Wintune 97 reports six performance scores-create file, sequential write, sequential read, random write, random read and delete file. For brevity's sake, we'll present the total of the six scores for both cached and uncached speed. If you'd like to see the complete Wintune test results, visit our Web site at http://www.winmag.com.

The cached speeds were all roughly the same (between 9MB per second and 9.7MBps), with the exception of the O.R. Technology a:drive, which relies on a completely different technology. (For a fairer comparison, we've reported the a:drive's test results separately.) The Fujitsu DynaMO was the fastest of the drives we tested, but only by a hair. It was a tenth of a second faster than the SyQuest SyJet 1.5GB (9.7MBps vs. 9.6MBps)

The drives in our group ranged in price from $149 for the Iomega Zip to $529 for the Micro Solutions backpack pd/cd with a sound card. But that's not the only cost factor you need to consider. In terms of cost per megabyte, the Olympus SYS.230 was the most economical (4.7 cents per megabyte) in our group of drives and the Avatar Shark 250 the most costly (16.5 cents per megabyte)

As far as capacity, the SyJet was the clear winner, coming in about half a gigabyte ahead of the nearest competition, the Iomega Jaz drive (1.429GB vs. 1.02GB). The skimpiest was the Iomega Zip drive, whose media holds only 95MB.

Now let's take a look at the specific differences among the four technologies-and among the eight drives.

You're not likely to make a purchase decision based on a given technology-each of these four standards offers basically the same advantages. Instead, examine the differences among the drives to see which features you can and can't live without.

Magnetic Media

The removable-media drives in the magnetic-media category are based on the technology employed in conventional hard drives or floppy disk drives. In the former, the read/write head "flies" above the magnetic disk surface; in the latter, the head makes physical contact with the diskette surface. In either case, data read and write operations are magnetic only, and similar in concept to the conventional audio magnetic tape recorder.

Avatar Shark 250

One fine example is Avatar Peripherals' Shark 250. We examined a beta version of the drive, which stores 250MB (unformatted) on a 2.5-inch removable cartridge. The drive's diminutive size makes it the perfect roadside companion-copy your important files to an Avatar cartridge, then take both medium and machine with you.

The Shark comes with a data cable that connects to your computer's parallel port, and the drive provides a pass-through D25 connector for a parallel printer so that both can share the port. An additional short cable fits any keyboard or OS/2 mouse port. Plug one end into either port, then plug your regular mouse or keyboard cable into the opposite end. A short lead from one of the plugs powers the Shark. If you plan on traveling with your Shark, you can add an optional PC Card interface.

An Auto Eject utility supports an option that lets you eject the media from as many removable-media devices as you have installed. You can select the media you'd like to eject when Windows 95 exits. Make sure you eject your Avatar cartridge before killing the power, because the drive must be powered on and connected to the parallel port for the eject mechanism to work. If you forget, remove both connectors, reinsert the power cable only and press the eject button.

The Shark will take a $299 bite out of your budget, while the media will munch $39. With a 236MB formatted capacity, cost per megabyte is 16.5 cents.

Iomega Jaz and SyQuest SyJet 1.5GB

Two more magnetic media drives that are similar in concept though not in details are the Iomega Jaz and the SyQuest SyJet 1.5GB. Both data cartridges house a 3.5-inch dual-platter system, but the cartridges are physically incompatible. The 1GB Jaz cartridge is just a trifle thicker than its 1.5GB SyJet counterpart.

The Jaz is easier to use. In fact, the Jaz was the most user friendly of all the drives in our group; just insert the cartridge as you would a conventional 3.5-inch floppy disk. On the SyJet drive, you have to hold open a hinged drop-down cover while pushing in the cartridge.

Both drives have two front-panel lights. Here, too, we preferred the Jaz, because both its indicators are bright and easy to read; one light is green, indicating power on, and the other is amber, indicating the drive is in use. The smaller SyJet indicators are both green. The in-use light turns amber when the drive is accessed, but it's not easy to spot this unless you're directly in front of the drive.

Both drives use high-density D50 connectors (stacked vertically on the Jaz and side by side on the SyJet). With little clearance between the two Jaz connectors, you have to find slim-profile cable connectors. Any SCSI cable from Granite Digital (510-471-6442) works well; otherwise, look at the connectors closely before you buy them.

On both drives, you set SCSI ID via twin push buttons; termination is automatic. The Jaz adds a three-position switch to set termination to always on, automatic or always off. The recessed switch is difficult to see-you may need a jeweler's loupe and a pointed instrument to make changes. And disregard the termination arrow just above the switch; it points in the wrong direction. When in doubt, note the adjacent green LED, which illuminates if termination is enabled.

The SyQuest Win95 utility includes a format option that recognized two drives on our system-the SyJet and an older SyQuest EZ135 drive we left in place during testing. The utility provides an intermediate test LED button. Click on it to make sure the correct drive is selected. An optional preformat data scan checks the disk for defective sectors, after which the format begins.

The two drives are $100 apart: $399.95 for the Jaz and $499 for the SyJet. The drives' media costs, however, are the same: $124.95 and $124.99, respectively. The real differences are in the capacity and the cost per megabyte. The SyJet holds a whopping 1429MB, bringing the cost per megabyte to 8.7 cents. The Jaz drive's smaller (but by no means unimpressive) capacity of 1020MB brings its media cost up to 12.3 cents per megabyte.

Iomega Zip drive

Iomega has another popular entry in the magnetic-media category: the Zip drive. At $149, this is the most economical of all the drives in our group. The cartridges are easy to procure at $14, but their limited capacity brings their cost per megabyte up to 14.7 cents.

The enclosure for the Zip drive's 3.5-inch single-platter cartridge is slightly larger and thicker than a conventional 3.5-inch diskette.

The Zip drive comes with a utility package that includes read, write and password protection, a long format option that adds a verify pass, and numerous other software bells and whistles.

The drive's rear panel has two female D25 connectors and a vertical slide switch for termination, which is on if the switch is in the down position. But it's easy to overlook this once you've attached a cable. Its connector obscures the embossed on symbol ("|"), and it appears as though on is up, as is usual with conventional on/off switches. An adjacent switch selects SCSI ID 5 or 6. You have no other choices, so if neither SCSI ID is available, you'll have to resolve the conflict at the other device. Another minor inconvenience is the absence of a power switch.

Phase-Change Rewritable

The phase-change medium shifts from the magnetic field to the field of lasers. It's derived from write-once, read-many (WORM) technology, in which a laser beam alters the molecular structure-and thus, the reflectivity-of the medium. As a result, a laser beam can detect the recorded 1s and 0s in a data stream, based on the alternating reflectivity of the medium. Unlike a WORM disk, however, you can write to a phase-change disk more than once.

The medium was originally dubbed phase-change disk (PCD), but later was shortened to PD-perhaps to prevent confusion with the complementary CD function found in some phase-change devices. Those devices are usually called PD/CD-ROM drives. The "PD" now has no official meaning, although some suppliers equate it with "Power Drive," "Plasmon Drive" (after the cartridge manufacturer) or just about anything else that can be abbreviated as "PD."

Micro Solutions backpack pd/cd

One example of a PD/CD-ROM drive is the Micro Solutions backpack pd/cd. It may look like just another CD-ROM drive, but the backpack accepts 650MB data cartridges as well as conventional CD-ROMs and audio CDs. If your system already has a CD-ROM drive, this may seem redundant. However, if you have one CD-ROM you always need on hand, it's a welcome redundancy.

The drive costs $449, but for an extra $80 you can add a sound card. This, too, may be redundant if your system is already set up for multimedia. In that case, save the money and a bit of configuration confusion by getting the silent version of backpack.

When you insert a data cartridge in the drive tray, the drive letter appears as the next available letter on your system. A CD-ROM will show up as the drive letter after that. The drive distinguishes between the media by means of a sliding sensor at the back of the tray; a front-panel light shows up red for data cartridges and green for CDs. It has a little difficulty with CDs, though. You have to make sure the CD is properly seated on the sensor, otherwise the drive won't recognize its presence.

The backpack's rear panel has two connectors-a male D25 for input from the computer, and a female D25 for pass-through to a parallel printer. Our evaluation unit also came equipped with a built-in sound card that handles MIDI, waveform and CD-audio formats. Rear-panel audio jacks include two line-level (line and aux) and one mike-level input, plus line- and speaker-level outputs and a separate CD-audio output jack. Support software has all the features that accompany most internal sound cards.

The backpack's cartridges cost $46. With a formatted capacity of 631MB, this works out to 7.3 cents per megabyte.


Combining both laser and magnetic technology, the magneto-optical drive might best be described as a laser-assisted magnetic device. You'll need to lay out more bucks per byte for a good magneto-optical drive, but the media costs less than comparable-capacity magnetic formats. It can also take more abuse, of both the physical and magnetic variety.

Although the underlying recording technology remains magnetic, the coercivity of the medium is typically an order of magnitude greater than that of conventional magnetic media. As a result, it's almost impossible to write to it with a conventional magnetic head. For recording, a laser beam raises the temperature (which lowers the coercivity) of a tiny area, enabling the area to be recorded. Once recording is complete, the coercivity returns to its normal state, making the medium virtually impervious to accidental erasure by stray magnetic fields.

Olympus SYS.230

We looked at two drives in this category. The first was the Olympus SYS.230, a combination SCSI and parallel port device that accepts ISO standard 3.5-inch 128MB and 230MB magneto-optical disks. This drive travels well in a briefcase, and the included parallel port accessory makes it convenient for laptop or other non-SCSI environments.

The drive has two D25 female connectors on its rear panel. Because termination is not automatic, you must set the correct mode via a small rear-panel slide switch. An adjacent green LED illuminates if termination is switched on.

Though the drive comes with a parallel pass-through cable and a conventional D25 cable, you'll probably need to buy an adapter to connect the SYS.230 to a SCSI chain. We used the D25-to-Micro D50 adapters that came with the Iomega Jaz system.

At $389, the SYS.230 isn't the cheapest drive, but the media cost is the lowest of all the drives in our group-only $10 for a 215MB-capacity cartridge. This also made the SYS.230 the most economical in terms of cost per megabyte-just 4.7 cents per megabyte.

Fujitsu DynaMO 640

Like the SYS.230, the Fujitsu DynaMO 640 accepts both 128MB and 230MB media, but it will also take 540MB and 640MB cartridges, which are available in regular and overwrite (OW) formats. Unlike conventional magnetic media, a magneto-optical write operation usually requires three passes-erase, write and verify. The OW medium, however, combines the erase and write actions in one pass. OW cartridge coding notifies the drive of this capability, which can improve write speed by 33 percent. With a cached speed of 9.7MB per second, the DynaMO was the fastest drive in our group, if only by a split second.

The DynaMO was also similar in cost to the SYS.230. The drive itself was one of the most expensive in our group, at $499. But the 640MB cartridges cost only $30, bringing the cost per megabyte for the 599MB formatted-capacity cartridges to 5 cents-second only to the Olympus SYS.230.

The rear panel of the DynaMO 640 has two Centronics 50-pin connectors, four DIP switches for setting termination and other parameters, and a rotary switch for SCSI ID number. Its MO Format utility supports both low- and high-level formatting, but the former shouldn't be necessary. You may find the utility confusing at first, because its Option menu lists only a single low-level format. But if you don't select this option, the utility does a conventional high-level format. An accompanying readme file warns that the system could hang if you use the regular Windows 95 format, but we had no problem with it during our tests.

We noted a few minor quirks. Although MO Format listed all removable-media drives, it failed to recognize their drive letters and reported that each housed an MO cartridge. The utility also had a habit of ejecting all removable-media cartridges as part of its exit procedure.


Like magneto-optical drives, floptical drives represent a merger of two technologies. But that's where the similarity ends. The floptical drive is usually backward-compatible-that is, it can read and write conventional 3.5-inch diskettes.

As its name suggests, the floptical drive combines floppy- and optical-disk technology, with an ultra-high density magnetic head that permits writing up to 20 tracks in the space formerly required for just one. Given the extremely fine physical tolerances required, an optical tracking system guides the head by reading a servo pattern laser etched into the media surface. You can reformat or bulk erase it without damaging the pattern.

O.R. Technology a:drive

One noteworthy example in the floptical category is O.R. Technology's a:drive. The a:drive accepts conventional 3.5-inch floppy disks as well as 120MB media, so you can swap out your floppy disk drive in favor of the a:drive. You can even configure the drive as a boot device if your system BIOS supports this feature.

The a:drive is slow compared to the other drives we tested (1.3MBps, as opposed to around 9MBps). Its three-pass write sequence makes it even slower than a standard floppy disk drive when you're using a 1.44MB floppy disk (0.12MBps for the a:drive vs. 0.27MBps for a standard floppy disk drive). But pop in one of its 120MB floppy disks and the a:drive leaves the floppy disk drive in the dust, surpassing its speed almost fivefold (see the chart "The a:drive vs. the Floppy")

And as an added incentive, the media cost works out to about 15.8 cents per megabyte, or about 30 cents less than a conventional floppy disk. The drive itself costs $210.

The a:drive connects to a standard IDE controller via the same flat cable an internal IDE hard disk uses. It took a bit of head scratching (to say nothing of assistance from O.R. Technology) before we figured out how to get Windows 95 to acknowledge the drive. We hadn't used the Dell Pentium's integrated IDE controller prior to these tests, so Windows 95 decided not to acknowledge its presence. Apparently, Win95 will find an IDE controller during the hardware-detection phase, but only if an IDE device is already connected to it. If you connect the device later, the Add New Hardware applet will find neither the controller nor the drive. But once we specified Standard IDE/ESDI Hard Disk Controller, Device Manager reported both items were up and running-and so were we.

O.R. Technology also makes an a:drive for notebook computers called the Slim Line a:drive, and an external unit should be available by the time you read this article. This along with the convenience of ultra-high capacity storage make the a:drive an attractive alternative drive. Only you can decide if the a:drive's advantages are worth the sacrifice in speed.

In fact, each of the drives we looked at comes with its own set of advantages and disadvantages. You need to determine what's most important to you.

The three key factors are price, capacity and speed. If capacity isn't an issue, but price is, you may want to consider the Iomega Zip drive. If capacity is key and you have the cash, consider the SyQuest SyJet 1.5GB.

Speed wasn't really a factor among the drives in our group, because the differences in this area were so slight. But if you're one of those people for whom every split second counts, snap up the Fujitsu DynaMO.

Other factors to consider include ease of use, portability and versatility. The Iomega Jaz was the easiest to use, and it's also no lightweight as far as capacity is concerned. If you're a road warrior, don't leave home without the Avatar Shark 250. If you like your gadgets to serve dual duty, consider the ambidextrous O.R. Technology a:drive, which doubles as a floppy disk drive, or the multifunctional Micro Solutions backpack, which accepts both data cartridges and CD-ROMs. The bottom line, with apologies to the Rolling Stones, is you can't always get everything you want, so get what you need.

Windows Magazine, July 1997, page 208.

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