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Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!mips!apple!ntg!slandrum
From: slandrum@ntg.uucp (Stephen Landrum)
Newsgroups: comp.sys.ibm.pc.hardware,comp.multimedia,comp.misc
Subject: Re: Diffs between DD & HD disks
Message-ID: <48@goblin.ntg.uucp>
Date: 8 Apr 91 19:52:23 GMT
References: <1991Apr6.170017.24990@news.iastate.edu> <1991Apr6.234019.2894@agate.berkeley.edu> <571@lysator.liu.se>
Reply-To: slandrum@ntg.UUCP (Stephen Landrum)
Followup-To: comp.sys.ibm.pc.hardware
Organization: New Technologies Group, Inc.  Palo Alto CA
Lines: 23

In article <571@lysator.liu.se> zap@lysator.liu.se (Zap Andersson) writes:
>THere is SOME thruth to this, however:
>
>Most diskette manifacturers use the same media for 1.44 and 720k disks.
>However, a test is done on each disk, and if it falls below a certain
>threshold in reliability, they go in the 720k bucket, otherwise they
>will become 1.44 Meg's.....
>
>Imagine this on memory chips.... if QA testing allows, they are 1Meg
>chips, if not, just 256k ;-)

Well, your reference to memory chips is not as silly as it seems.  Back
when RAM was expensive, Atari sold 8k boards for their Atari 800 computer
which were filled with 16K RAMs that had errors in only one half of the
address space, and one of the address lines would be tied low or high
depending on which half was bad.



-- 
Stephen H. Landrum                                        VOICE: (415) 813-8909
                    UUCP: ...apple!ntg!slandrum
 USNAIL: New Technologies Group Inc. 2468 Embarcardero Way, Palo Alto CA 94303