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From: chao@tornado.Berkeley.EDU (Chia-Chi Chao)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Some of Seagate's ST251-1's running at 40ms
Message-ID: <1990May8.162703.10766@agate.berkeley.edu>
Date: 8 May 90 16:27:03 GMT
References: <1806@nems.dt.navy.mil> <13489@ucsd.Edu>
Sender: usenet@agate.berkeley.edu (USENET Administrator;;;;ZU44)
Reply-To: chao@ocf.Berkeley.EDU (Chia-Chi Chao)
Organization: ucb
Lines: 16

In article <13489@ucsd.Edu> steve@wintermute.ucsd.edu ({Darkavich}) writes:
>In article <1806@nems.dt.navy.mil> scherer@dtrc.dt.navy.mil (Doug Scherer) writes:
>>     I've purchase about 20 Seagate ST251-1 drives and found that they all
>>     worked well but when I ran benchmarks on 3 of them they were really
>>     ST251 (40ms) drives.  The cases were marked as -1's though.  
>
>The first is to make sure you have a 1:1 interleave controller card in your
>computer.  If you do then you need to make sure that the hard drive was
>low-level formated with an interleave of 1:1.

If I understand it correctly, the 28ms rating (251-1) is the average seek time
-- how fast the drive can move the heads.  It is the physical limitation of
the drive and has nothing to do with the interleave factor, although both
affect the throughput.

Chia-Chi     chao@ocf.berkeley.edu