Hi,

I can't get this machine to run a FSB over 160Mhz.

Any ideas why?

It will run Memtest86 error free at 168Mhz, but in W2K the max appears to be 160Mhz.

The RAM is 2 x 256MB TwinMos DDR3200. The CPUs are XP 2600s (i.e FSB 166) modded to MPs.

I'm getting around 1 error in Prime in 8 hours; but if I bump the FSB upto 166 the system is seriously unstable.

BTW: ANybofy know how to get Prime95 to use both CPUs, or run two instances of it? I'm running a second app to soak up the other CPU while running Prime.

I'm trying to figure where the bottleneck is, and what to do about it.


First Possibility: AMD 762 System controller

Maybe that only really gets stressed when actually using both CPUs, which would explain why its OK at 168Mhx in Memtest86.

I've replaced the heatsink on the 762 with a bigger one, plus a fan, and it seems to run cooler. It was definately warm before.

Does anybody know what voltage it runs off?


Next Possibility: PSU

Chieftech 350 Watt. Should be enough. AsusProbe shows good voltages.


Third Possibility: PCI/AGP speed.

Seems trhere may be no way to fix or control the PCI/AGP speed. Seems surprising...



Any other ideas?



Peter