Path: utzoo!attcan!uunet!snorkelwacker!apple!portal!cup.portal.com!Lou
From: Lou@cup.portal.com (William Joseph Marriott)
Newsgroups: comp.sys.mac.misc
Subject: Re: Formatting 800k as HD ?!?
Message-ID: <30281@cup.portal.com>
Date: 29 May 90 01:07:04 GMT
References: <35018215MES@MSU> <21943@dartvax.Dartmouth.EDU>
  <10957@pucc.Princeton.EDU> <9546.2652d2ce@amherst.bitnet>
  <34@hite386.UUCP>
Organization: The Portal System (TM)
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Boy, this is really depressing, the amount of misinformation about these
drives and disks. Especially since many of the posters seems to be the
kind of folks novice users look to for advice. Well, here's some honest
facts and prudent rules:
 
1. Single-sided diskettes should be formatted at single-sided. Double-sided
diskettes should be formatted as double-sided. High-Density disks should be
formatted at high density. Mac disks should be formatted on a Mac. PC disks
should be formatted on a PC, or on an FDHD Mac running Apple File Exchange.
 
2. Never mutilate a disk you intend to later use. Mutilation includes, but
is not limited to: drilling, soldering, bending, cracking, prying, polishing,
immersing, flipping, and melting disks.
 
3. You can use tape and certain kinds of hardware to format a high-density
disk as 800K or 400K. Even if this operation seems to work, the disk will
behave unreliably, and will ruined for high-density use. To put things in
English terms, imagine diskettes are like multi-lane highways, and that
your data is represented by different colored cars. An 800K disk has wide
lanes and large cars, so fewer cars can fit on the highway at any time. An
HD disk has very narrow lanes and tiny cars. Now,if you try to format an
HD disk as 800K, you wind up putting wide cars on narrow lanes. The effect is
that it is not always clear which lane a given car is in. Imagine the traffic
problems that would ensue if no matter what you did, you would always have
part of you car in someone else's lane. Imagine how flaky your disk will
behave if you format it for a different density.
 
4. The magnetic field holding together data on an HD disk is weaker, and
thus more susceptible to the things all disks are susceptible to.  Under
the rigors of typical college life, an 800K didk is probably more reliable.