i7 920 c0 keeps dropping to 12x multi after 11mins of stress test

[geoc]

I have trouble maintaining and overclock speed when under stress. So I set my CPU to a specific speed, and surely enough it boots at that speed. But the real problems is when it drops to 12x multi after 11mins or so of prime95. Once I stop, the multiplier goes back to normal. And I start stressing it again, and it runs at full speed for 11mins or so and starts dropping the multi again.

I have disable all possible power management including turbo boost to no avail.

Underload, the highest temp for any of my cores do not exceed 77C

Anyone have this problem or know how to solve it?

[Birk]

Sounds like self throtteling at 75c to me.

[geoc]

I've heard of thermal throttling at Tj Max, but not self throttling. How do I disable it?

[geokilla]

Double check that all power management are disabled.

Ensure that the cooler is making proper contact with the CPU and you have enough AS5 or whatever.

[Feanor]

Originally Posted by geokilla

Double check that all power management are disabled.

I would start with that. Disable all s state, speedstep and every power option ( i like to keep the throttling if the cpu goes in the tjmax zone, like when your pump decide it don't want to start with the system...). That really looks like power management problem.

[geoc]

yea, I've made sure everything was disabled and it still dropped to 12x multi. Funny enough, if I raise the clock speed even more, the problem goes away.