Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!crdgw1!sixhub!davidsen
From: davidsen@sixhub.UUCP (Wm E. Davidsen Jr)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: Why buy a DX over an SX?
Message-ID: <3787@sixhub.UUCP>
Date: 24 Apr 91 03:48:08 GMT
References: <14534@encore.Encore.COM> <1991Apr12.162615.13529@holos0.uucp> <1991Apr21.203004.9909@unlv.edu> <1991Apr23.000348.6644@kessner.denver.co.us>
Reply-To: davidsen@sixhub.UUCP (bill davidsen)
Organization: *IX Public Access UNIX, Schenectady NY
Lines: 22

In article <1991Apr23.000348.6644@kessner.denver.co.us> david@kessner.denver.co.us (David Kessner) writes:

| The ISA bus has no baring on the performance of the CPU.  On ALL 386 (DX or SX)
| systems the memory is not accessed over the ISA bus, but rather has it's own
| 'memory bus'.

  There are a large number of SX motherboards which only have 8MB on the
board. This is fine for DOS, but falls somewhat short for UNIX. The
expansion memory is then put on the ISA bus, with one total w/s at any
practical speed.

  People do run memory on the ISA bus, and cache makes a huge
difference.

  Also, all the early DX boards had a 4MB limit on the motherboard. This
system is running 8MB on the ISA bus, and it may be slow but it beats
paging!
-- 
bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen)
    sysop *IX BBS and Public Access UNIX
    moderator of comp.binaries.ibm.pc and 80386 mailing list
"Stupidity, like virtue, is its own reward" -me