Cyrix 6x86MX PR333 CPU on ECS P5ST-A

Recommended by Wim's BIOS...

by **jamsah** » Tue Sep 28, 2004 12:09 am

Dear All,

My Cyrix 6x86MX PR333 CPU (83MHz Bus 3.0X) does not work when Bus Clock Setting jumper set to 3 and Bus/Core Multiplier Setting jumper is set to 3. That's, 83MHzx3 = 249MHz(PR333). PC boots boots up first. Then somewhere after the first POST sceen into Windows startup 'registry problem ...' or similar error message appears then disappears (sometimes after I press a key (sorry I can not remember)).
Windows continues loading ... all the way to the main Desktop.

But then, suddenly (and sometimes immediately) 'Windows Registry Problem ... Restart You Machine' or similar error message appears. Here, the only option is to click OK which restarts my PC. It then goes ALL over again!

At the moment I am running at 75MHzx3 = 225.5MHz (PR300).
But I want to utilise this higher 83MHZ FSB that my CPU supports.
And my m/b supports (according to Time Computers who got it TERRIBLY wrong the MAX RAM this m/b supports) 66MHZ, 75MHZ and 83MHZ bus speeds. My m/b did not come with any manual. Only with user folder Full of Errors and designed for ALL ECS boards by Time!
And the same is true if I try to find any info of this m/b from ECS/Elite, on the WWW or anywhere else.

Any help from anyone, please.

CPU overheating? Or am I missing something eg FSB setting etc?

by **Denniss** » Tue Sep 28, 2004 2:11 am

AFAIK your mainboard does officially support only 75MHz FSB - 83MHz is not guaranteed .
With relaxed memory timings it might work or not .

You might want to try 3.5x multiplier to get PR333 back - lower FSB but more MHz to compensate

Check www.motherboards.org for a manual - maybe linked in one of the Forum sections or via their download/Motherboard section

by **jamsah** » Tue Sep 28, 2004 5:49 pm

Thanks for this suggestion.
But I tried it first. It works but machine becomes VERY unstable - always crashes, freezes, restarts Windows etc etc etc. I think the CPU is getting too hot and can NOT operate at this MAX speed.
So, I wanted lower MHz with higher FSB to achieve a similar performance

Denniss wrote:AFAIK your mainboard does officially support only 75MHz FSB - 83MHz is not guaranteed .
With relaxed memory timings it might work or not .

You might want to try 3.5x multiplier to get PR333 back - lower FSB but more MHz to compensate

Check www.motherboards.org for a manual - maybe linked in one of the Forum sections or via their download/Motherboard section

BiosMan · by **KachiWachi** » Wed Sep 29, 2004 2:10 pm

Does this board use SIMMS or DIMMS?

If SIMMS, can your RAM take the 75 or 83MHz bus that you are throwing at it?

by **jamsah** » Wed Sep 29, 2004 3:12 pm

The board can use both.
But, at the moment, only 4x32MB 72-Pin EDO SIMMs installed.
Speed of RAM = 60ns. See typ spec from Crucial.com:
CT8M32E2M6 EDO • Non-parity • 60ns • 5V • 8Meg x 32

Now, do you think my RAM can take the 83MHz FSB?
And how can check this??

KachiWachi wrote:Does this board use SIMMS or DIMMS?

If SIMMS, can your RAM take the 75 or 83MHz bus that you are throwing at it?

by **Denniss** » Wed Sep 29, 2004 4:38 pm

I have 60ns EDO ram running fine with fastest timings on 75MHz but I have 60ns EDO that does not like 75MHz at all .

Try the lowest possible memoy timings and try 83MHz FSB . If this doesn't work stick to 75MHz - try to get better cooling for some additional Mhz

by **jamsah** » Wed Sep 29, 2004 5:30 pm

Denniss wrote:Try the lowest possible memoy timings and try 83MHz FSB . If this doesn't work stick to 75MHz - try to get better cooling for some additional Mhz

Where can I set the memory timings, please? In BIOS?

by **Denniss** » Wed Sep 29, 2004 11:59 pm

jamsah wrote:
Denniss wrote:Try the lowest possible memoy timings and try 83MHz FSB . If this doesn't work stick to 75MHz - try to get better cooling for some additional Mhz

Where can I set the memory timings, please? In BIOS?

Yes in Bios
-> please read the manual or Bios optimization guides available in the net