Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!uakari.primate.wisc.edu!zazen!uwvax!persoft!dag
From: dag@persoft.com (Daniel A. Glasser)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: Speed of memory off motherboard
Summary: 32 bit expansion cards not at I/O bus speed.
Message-ID: <1991Jan24.180048.23480@persoft.com>
Date: 24 Jan 91 18:00:48 GMT
References: <2731@cod.NOSC.MIL>
Organization: Persoft, Inc.
Lines: 20

In article <2731@cod.NOSC.MIL> burkley@cod.nosc.mil.UUCP (Joe Burkley) writes:
>I have been following a discussion in the MS Windows group
>regarding a performance degradation which seems to be traced
>to having memory in an expansion card.  My system is a 33 Mhz
>386 which has 4Meg on the motherboard and has the option to
>drop and additional 12 Meg in a 32 bit expansion card.  My 
>question is will the memory in the expansion card suffer from
>a slower access time than the motherboard memory?  Email
>replies are fine.

This speed degradation is linked to memory on ISA (16-bit) or 8-bit slot
expansion boards.  The 32-bit memory expansion slot does not have this
problem, since it is a full 32-bit buss running at full memory buss speed.
(Actually, it is an extension of the on-board memory buss in most cases.)

So, no, memory on the 32 bit expansion card will not degrade system
performance.
-- 
          Daniel A. Glasser  |  Persoft, Inc.  |  dag@persoft.com
                "Their brains were small, and they died."