Problem with Prime95 Very Strange!

[Mman13]

Hi all.

 

I recently installed VS1GBKIT400 in dual channel for my Shuttle An35n Ultra motherboard. I am running a locked 2600+ Barton.

 

Memory is passing Memtest86 for 5+ hours no problem. However, when I attempt to run Prime95 it fails to peg CPU usage to 100% it just sits at test one. I use Speedfan to watch Cpu usage and it fluctuates from 1% to about 25% sometimes reaching 100% ,but will not stay. Prime95 is just stuck as it cannot test the limits.

 

I have tried a huge selection of different FSB's, Vdimm's and V'cores all to no avail. I have tried running them in single channel seperately also. Still with the same results. My old Ram will operate Prime95 without any problems at all CPU usage will peg at 100% and it will run that way for 8+ hours.

 

Anyone who can shed a little light my way would be awesome. I'm pulling my hair out here.

 

Thanks!

[RAM GUY]

Can you tell me the CPU speed and it’s FSB as well? In addition, please tell me the bios settings you have set for both CPU and memory and any performance settings that you may have set?

And you should be running the memory at DDR333 so it's in sync with your CPU and I would suggest 2.7 Volts for memory voltage.

[Mman13]

Thank you Ram guy. I have the problem sorted out. I sent an email to Prime95 and got a fast responce. This is CPU Thrashing and has nothing to do with the hardware itself. It is a bug with prime. I was instructed to run a custom torture test and decrease the memory to be tested from 927 to 850 and it runs fine! Passed the torture test yesterday for 9+ hours. 1gb kit of value select running in dual channel.

 

Locked Barton 2600+ has been slightly OC'ed to 2105MHz.

FSB 183

Vcore 1.775

Vdimm 2.6

Mem Freq 100%

2.5-3-3-11 timings. ( seem to work better with the nvidia2 chipset )

 

Running Memtest86 and Prime95 stable!