Path: utzoo!news-server.csri.toronto.edu!helios.physics.utoronto.ca!ists!yunexus!rreiner
From: rreiner@yunexus.YorkU.CA (Richard Reiner)
Newsgroups: comp.unix.sysv386
Subject: Re: IDE Drives
Keywords: interactive hard disk IDE
Message-ID: <21870@yunexus.YorkU.CA>
Date: 12 Mar 91 15:16:39 GMT
Organization: York U. Computing Services
Lines: 16

lam@hyper.hyper.com (Edmund C. Lam) writes:

>The drawback with IDE comes from the fact that the interface limits
>your data transfer rates to an observed maximum of 400K/s.  
>The drive might be quick on average access time, but IDE drives 
>suffer from low transfer rates.

As a generalization, this is false.  I have observed 950 Kb/sec from
IDE drives on ISA 386-33 machines.

However, it is no doubt true that higher data transfer rates can be
obtained on ISA with bus-mastering DMA techniques, such as those used
by the better SCSI controllers, than with the PIO approach used by
IDE.  But the limits of PIO are not nearly as low as Lam suggests.

//richard