Originally posted by: Rubycon
Originally posted by: tornadog
I had my Opteron running at 350 x 8(1.5V) on my box running XP SP2. During summer I had set it back to 250 x 9(1.35V) because of high ambient temperatures. Anyway I upgraded to Vista since then and yesterday, I was trying to overclock for the first time in Vista. The system booted fine at 350 x 8 but in Vista, it gave me mutiple errors like SVHost has to close, network Conenctions has to close, etc. Finally when I tried opening the control panel, I got a BSOD with DRIVER IRQ less or not equal error. I set it back to 250 x 8 and now its working fine. I have also tried different other Mhz and multipliers but nothing above 250 seems to be working.
Overclocking is all about margin. All cpu's have plenty of margin at the default speed. This allows for reliable operation in high ambient temperatures, dust on cooler fins, failing fans, etc.
You can run on lower margin and achieve higher speeds but that comes at the risk of crashing if you breach that absolute max speed the cpu will run at. It would appear that your original overclock that you settled upon was too close to the margin limit as evidenced by having to turn things back with higher temps. Newer operating systems with their increasingly complex requirements/ios, etc. WILL stumble if the system has a problem.
I've overclocked many systems that could run desktop applications for weeks and even play games or run 3DMark. A serious stress testing program like PrimeSMP or OCCT would crash in seconds, however. For a much higher success rate in overclocking, find the limits of the hardware and back off a few notches so you still have some margin for higher temps. (and sticky things like Vista hehe!)