CPU unstable in 3dmark but rock solid in CPU Stress test

[dmw16]

I have a Palimino XP1800+. I know that the new Tbred cores are better, but I got that chip...well I guess it was a year ago now. Anyway, I got my Epox 8RDA and decided it was time to start overclocking. I got a CPU unlocking kit but I had no luck unlocking my cpu. But it is such a pain to disassemble the thing because I have an Alpha 8045 heatsink. So i decided to just overclock using my FSB. Anyhow, I started working my way up and found that I could run at 1702Mhz @ 148Mhz FSB. I did several tests. I ram Prime95 for 24hours then ran this other test, i think it is just called CPU Stress Test. It is one that lets you make a stability certificate after you run it for 24hours. Anyhow, I was happily running along at my 1702Mhz. Then, the other day, my new video card arrived (my last one died and I was overclocking to keep myself busy before I could play games again). So I put my new Radeon9500 in and started up 3dmark. The system barely made it through the first test before it restarted or locked. So I turned the CPU down to stock to make sure it wasnt my card and everything was fine. Why would 3dmark make my O/C cpu have probs when prime95 and the like dont? I guess I could try more voltage. Any ideas?
thanks,
-doug

 

[Boogak]

Did you lock your AGP bus speed to 66mhz?

 

[Duvie]

Originally posted by: dmw16
I have a Palimino XP1800+. I know that the new Tbred cores are better, but I got that chip...well I guess it was a year ago now. Anyway, I got my Epox 8RDA and decided it was time to start overclocking. I got a CPU unlocking kit but I had no luck unlocking my cpu. But it is such a pain to disassemble the thing because I have an Alpha 8045 heatsink. So i decided to just overclock using my FSB. Anyhow, I started working my way up and found that I could run at 1702Mhz @ 148Mhz FSB. I did several tests. I ram Prime95 for 24hours then ran this other test, i think it is just called CPU Stress Test. It is one that lets you make a stability certificate after you run it for 24hours. Anyhow, I was happily running along at my 1702Mhz. Then, the other day, my new video card arrived (my last one died and I was overclocking to keep myself busy before I could play games again). So I put my new Radeon9500 in and started up 3dmark. The system barely made it through the first test before it restarted or locked. So I turned the CPU down to stock to make sure it wasnt my card and everything was fine. Why would 3dmark make my O/C cpu have probs when prime95 and the like dont? I guess I could try more voltage. Any ideas?
thanks,
-doug

"prime" expample why prime95 is not ans should not be the sole tester of system stability....The ocing is definitely the issue and not necessarily the cpu's fault...You have ram that gets clocked faster as fsb is raised, the mobo chipset, and any pci/agp device if it is unlocked....