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Chapter 7. High-Capacity Floppy Disk Drives


Many vendors have tried and failed to
establish a standard for a high-capacity FDD. All these so-called
superfloppy drives have suffered from some combination of
nonstandardization, incompatibility with standard diskettes, lack of
boot support, expensive media, small installed base, lack of OEM
acceptance, low reliability, and poor performance.

Iomega Zip Drives and, to a lesser extent, Panasonic SuperDisk
(LS-120/LS-240) Drives have sold in moderate numbers, especially in
some niche markets. Others, such as the fast, 200 MB Sony HiFD and
the Samsung Pro-FD, had features that compared favorably to the Zip
Drives and SuperDisk Drives, but either never shipped in volume or
were not adopted in numbers large enough to reach critical mass. The
story of high-capacity FDDs has largely been one of too little, too
late, and too expensive.

The ubiquity of inexpensive, fast, reliable CD-RW drives has
effectively killed the market for high-capacity FDDs except in
specialized niches such as prepress graphics work, which remains a
Zip Drive stronghold. In what may be the final straw, Iomega settled
a class action lawsuit in spring 2001 filed on behalf of those who
had purchased Zip Drives between 1995 and 2001. In settling that
lawsuit, Iomega in effect admitted that Zip Drives and discs were
unreliable, which doesn't bode well for the
continuing existence of the Zip Drive.

All of that said, there are a (very) few applications in which
high-capacity FDDs make sense, so we'll spend this
short chapter talking about them. A high-capacity FDD is a reasonable
choice in the following situations:



    You frequently need to transfer files
    larger than will fit a standard FDD between systems that are not
    networked and are not equipped with CD writers. For example, you need
    to move work files back and forth between home and office, or between
    a notebook system equipped with an internal high-capacity FDD and a
    desktop system.

    You receive files from people who have a high-capacity FDD but not a
    CD writer. That, of course, is increasingly uncommon, as CD writers
    have become ubiquitous.

    You have a "guest computer" for use
    by visitors who carry their work with them and need access to a
    computer to make on-the-fly, last-minute changes to their work. Using
    a high-capacity FDD on such a machine minimizes the footprint of
    multiple casual users and is easier to support than a CD writer.

    If your corporate mail system is slow or limits the size of file
    attachments, a high-capacity FDD can be used to
    "sneakernet" files between
    departments that do not share servers or mapped drives on the
    corporate network.

    Per Iomega's suggested uses for its Zip Drive, you
    can "Store encoded secret files before you hand them
    over to Russia." (We are not making this up.)


Table 7-1 lists the key characteristics of Iomega
Zip Drives and Panasonic SuperDisk Drives with CD-R/RW shown for
comparison. Transfer rates and access times are the best available,
and may be inferior for some interfaces and drive models. Prices are
approximate in US$ and are current as of July 2003.

Table 7-1. Key characteristics of high-capacity FDDs, with CD-R/RW shown for comparison

Zip100


Zip250


Zip750


LS-120


LS-240


CD-R/RW


Native capacity (MB)


100


250


750


120


243


700


IDE/SCSI/Parallel/USB



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Rotation rate (RPM)


2,945


2,945


3,676


720


1,500


variable


Average read access (ms)


39


39


37


112


65


65


Sustained transfer (MB/s)


1.4


2.4


7.3


0.2


0.4


7.2


Typical drive cost


$60


$75


$100


$100


$180


$75


Media cost (per cartridge)


~ $7


~ $9


~ $12


~ $8


~ $10


~ $0.20


Media cost (per gigabyte)


~ $70


~ $36


~ $16


~ $65


~ $40


~ $0.29


Bootable








Read / Write 1.44 MB?


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CD-R/RW is clearly a better choice for most uses, particularly when
media cost is an issue. Zip Drives and SuperDisk Drives do have some
advantages, however:

    Zip Drives and LS-120 SuperDisk Drives are a bit more convenient to
    use than CD writers and slightly faster if you need to write only a
    few small files. A CD writer is faster if you need to write a large
    amount of data.

    SuperDisk Drives can read and write 1.44 MB diskettes, so a machine
    with a SuperDisk Drive doesn't need a standard 1.44
    MB FDD, assuming the system BIOS supports booting from a SuperDisk
    Drive.

    LS-240 SuperDisk Drives support FD32MB technology, which allows
    formatting a standard 1.44 MB diskette as a write-once 32 MB
    diskette. Although that sounds like an attractive way to recycle old
    1.44 MB diskettes, FD32MB diskettes can be read only in LS-240 drives
    and their reliability is questionable, particularly for long-term
    storage.

    Unlike a CD, a Zip disk or SuperDisk disk fits in a shirt pocket and
    is protected by its case and shutter.



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