By Rich Levin

Your multimedia presentation for the sales conference is ready to go-but that 1.44MB diskette isn't equal to the task.

Or you're conscientiously backing up your hard disk, and suddenly you realize that you have too much of a good thing. Four years ago, when your hard disk held 200MB, you could back up with a QIC-80 tape drive and a couple of tapes. But that new 2-gigabyte hard disk would quickly consume a teetering stack of QIC-80 cassettes.

Maybe you're just tired of LapLink cable chaos. Transferring big files from your desktop to your laptop requires a tangle of plastic connectors, as well as the patience of a Zen master.

If you need a simple way to create large, mobile files, today's removable-media drives are just the ticket. With capacities from 135MB into the gigabytes, inexpensive removable storage has come of age, with major vendors such as Iomega, SyQuest and Compaq battling for your bucks.

Iomega fired the first shot in the removable-media war when it introduced its Zip drive in June of last year, and its newest item, the Jaz drive, looks to be an even bigger hit. The Jaz drive uses removable, slender 3.5-inch hard disk cartridges that hold 1GB and perform as fast as conventional high-end hard disks.

Check the specs: Dual-platter 3.5-inch Winchester media, 6.75MB per second data-transfer rate, 10MBps sustained burst mode and less than 12-millisecond access time. The Jaz makes storing masses of data as easy as working with floppy disks. All this for $499, with 1GB cartridges costing about $100.

The Jaz external drive supports Fast SCSI-2 connections and the internal drive allows both Fast SCSI-2 and IDE connections, making it a great choice for both Mac and PC users. The Jaz performs like a conventional hard drive, with one exception: Touch the eject button, and Jaz's motorized ejector hands you the disk.

If you're a heavy user of digital audio and video, the Jaz is hard to beat. Because it retrieves data as quickly as a conventional drive, audio and video run as smooth as silk. Some progressive souls look to the Jaz as a replacement for costly RAID arrays and slow CD-ROM towers.

If you're buying a new PC, look for one with a preinstalled Jaz drive. Many manufacturers-including Micron, Power Computing, Glyph and Promax-are already including Jaz drives in their systems. Typically, it adds anywhere from $400 to $600 to the cost of the system.

Industry leader SyQuest has engineers working overtime on its potential Jaz killer: the SyJet, due in stores late this summer.

The SyJet resembles the Jaz in several ways. It features a slim-line case and will support IDE and SCSI connections; the SyJet also adds parallel-port connectivity. It is expected to cost $499. The SyJet will deliver higher storage capacity (1.3GB), and its maximum data-transfer rate of 7MBps is close to the rated speed for the Jaz. Manufacturer-claimed seek times for the two products are also similar, with less than 11ms for the SyJet vs. less than 12ms for the Jaz.

Maybe you don't need a whole gigabyte of removable storage. Perhaps you're just looking for a little more capacity than the tiny 1.44MB that a floppy delivers. High-capacity floppy disks could be your solution. Iomega's Zip drive looks like a floppy disk but it delivers 70 times the storage capacity of a floppy-100MB, uncompressed. A magnetic head that floats on a microscopic cushion of air reads the disk. Air pressure prevents the head from impacting the media while allowing rapid data access. And the disks aren't proprietary-Sony recently started manufacturing Zip media, with a $19.95 suggested retail price.

The Zip drives read and write data at 1.4MBps, compared to 500KBps for conventional floppies, and are also easy to connect. It's a simple matter to hook up a Zip drive to your printer or SCSI port, and you can use the drive on both desktop and notebook PCs. Iomega recently announced a portable battery pack, making the Zip a truly mobile solution.

Iomega's OEM partners-Hewlett-Packard, Micron, Mac clone Power Computing and Escom Europe-have announced their intention to preinstall Zip drives in their basic PC designs by the third quarter. Expect more leading PC makers to join the party if Zip-ready PCs gain consumer and commercial acceptance.

With 1 million Zip drives and 10 million Zip disks sold, Iomega is clearly the leader in removable personal storage. There could be a challenger, however. Compaq, Matsushita and 3M have jointly developed a new high-speed 120MB floppy drive called the LS-120. Its data transfer rate is similar to a Zip drive. Compaq is now preinstalling the drive on select models.

Tried and True

If moderate capacity is your only requirement, Iomega's Bernoulli drives are an excellent alternative to the new technologies. The Bernoulli drive is the Zip drive's granddaddy. Bernoulli cartridges hold up to 230MB.

Iomega offers a dual-drive Bernoulli subsystem, which means you can have two cartridges live at all times. This makes it easy to duplicate cartridges for backup or distribution.

SyQuest also offers moderate-capacity removable cartridge drives that are the de facto standard for large graphic and audio files.

Virtually all SyQuest offerings are true hard drives-no accelerated floppy technology here. Winchester technology means SyQuest's drives are faster-given the Winchester drive's relatively faster access and seek times-in some instances, faster by one or more orders of magnitude when compared to other forms of storage. However, sometimes Winchester drives are less reliable than Bernoulli technology.

The EZ135 drive is SyQuest's Zip-contender. It's a 135MB removable cartridge with parallel, IDE and SCSI versions. Because it's a hard drive, it outstrips Zip in performance with an access time of 13.5ms, compared to Zip's not-so-zippy 29ms. The EZ135's sustained data-transfer rate is better-SyQuest claims 2.4MBps to Zip's 1.4MBps. SyQuest drives are available in a variety of capacities, from the EZ135's 135MB, to the SyJet, with 1.3GB.

Of course, there will always be those who lust for ever-larger data warehouses. For the elite users who can afford them, magneto-optical (MO) drives are a functional solution.

MO drives have capacities ranging from 230MB to 4.6GB. They're more expensive per megabyte than other forms of mass storage. A Pinnacle Micro Tahoe 230MB optical drive is sold by the manufacturer for $499. That's the same price as a Jaz drive, which has five times the capacity. On the other hand, Jaz cartridges, at close to $100, cost about two and a half times as much as a $39 MO cartridge.

MO drives are also slower than floppies, with access times hovering around 38ms and data-transfer rates ranging from 600KB per second to 1.75MBps. They're also notoriously unreliable, delivering 50,000-hour mean time between failure (MTBF). The average hard drive goes 500,000 hours-10 times longer.

MO has distinct advantages, however. At the top of the list: MO drives don't crash. The optical media is read by a laser and never physically contacts the read/write heads. Huge storage capacities-such as Pinnacle Micro's new 4.6GB Apex drive-make optical drives the sole choice for storing movies, music and other big data.

The advent of removable storage ushers in a new era of data management. Computer users now have a single affordable medium for all their storage, backup and data-sharing needs.