On  3 Dec 98 at 11:55, Jacobs, Laurie wrote:

> I have also been trying to overclock a Cyrix PR200 which my
> motherboard (a P5V580-B with 580VPX chipset) will let me use 2 x
> 75mhz or 2½ x 66mhz.

  2x75 is normal for a PR200.

> The problem comes when I try to run it at 2½ x 75mhz, The system
> reports it as a Cyrix PR233 and boots OK and works in DOS mode but
> Windows (95) won't load. It just freezes at the splash screen. I
> have tried re-installing W95 but same problem persists.

  This is a common point of failure for CPUs that are being
overclocked a little beyond what they're capable of.  You *might*
have better luck with additional cooling, but there's (of course) no
guarantee that you'll see any improvement.

> By the way, I can't find a manual for my motherboard, which makes
> changing jumper setting a real pain

  This is the EFA "Viking 1" board -- I have one, and so does my Dad.
It has been replaced in stores by the "Viking II" (P5VPX97).  You can
find a manual at

http://www.efacorp.com/download/manuals.htm

NOTE:  My board and my Dad's both came with manuals whose cover said
"Version 1.1".  I have seen a board whose manual said "Version 1.0";
I was unable to get that board to work, and exchanged it for a Viking
II.  I did not notice obvious physical differences between these
boards, but I expect the online manual to be 1.1, and if your board
is 1.0 then a few details may not quite match.

David G

         The PCBUILD web site always needs good submissions.  If
          you would like to contribute to the website, send any
               hardware tech tips or hardware reviews to:
                           [log in to unmask]