Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!helios.physics.utoronto.ca!ists!yunexus!xrtll!silver
From: silver@xrtll.uucp (Hi Ho Silver)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: Change clock speed on 386SX motherboard?
Message-ID: <1991Jan5.192126.11256@xrtll.uucp>
Date: 5 Jan 91 19:21:26 GMT
References: <1991Jan5.040434.15650@d.cs.okstate.edu>
Reply-To: silver@xrtll.UUCP (Hi Ho Silver)
Organization: Yeah, right.
Lines: 25


   It likely depends on the design of your motherboard.  There are several
parts which are speed-sensitive:

- the 386SX; as you propose to replace this with a 20 MHz part, this isn't
  a problem
- the chipset; as yours claims to work up to 20 MHz, this isn't a problem
  either
- the memory; I believe you were considering upgrading this as well.
- the expansion (ISA) bus.  The standard for this bus is 8 MHz.  Many
  (most?) cards will reliably run faster than this, but some won't.  If
  the bus is driven from the same crystal as your CPU (it might or might
  not be, depending on the whims of the motherboard designers), then going
  to 20 MHz would increase your bus rate to 10 MHz, and may or may not
  cause problems.
- the board design; chances are everything else will run OK at 20 MHz, but
  it isn't necessarily guaranteed.

   Also, increasing your clock speed may affect radio emissions from your
box.  This may or may not be a concern for you.
-- 
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