I've been trying to overclock my I7 920 to 3.6 GHz by changing the block speed and multiplier. I've left things like voltages alone for fear of screwing that up and I don't intend to push the CPU beyond 3.6 GHz.
Yet anytime I test my CPU under 100% load using a program like Prime95 or this other Intel specific one, I'm getting temperatures that seem too high. I have a Thermaltake V1 heatsink installed with the fan speed set pretty high. Besides for that I have two large case fans that I'll have to dig up the specs for later. I do the best to keep the airflow clear too. Yet when I'm running these stress tests the temperature all too quickly passes the shutdown threshold of 90°c I set up.
Now I understand this isn't a top of the line heat sink, but these temperatures seem too much when you consider that many people seem to push the I7 series to 4 GHz. I hope to God I didn't screw up back when applying thermal paste. It was incredibly stressful just installing the thing because of the amount of force you have to apply, I can't imagine repeating the process.
I'll do a stress test at default CPU speeds when I get a chance, but any ideas?
You don't say what kind of motherboard your using, but many motherboard default settings for voltages is "Auto". Auto means that the motherboard will attempt to adjust the voltages based on the clocks speeds that are set. If these options are set to auto, then your motherboard might be increasing voltages.
What kind of i7-920 do you have? The original "C0" stepping models can generate a lot of heat when you attempt to overclock them. I have a C0 i7-920 and it does not overclock very well at all.
Open cpu-z and tell us what the voltage under load is. I'll take a guess and say 1.25ish. That is simply too much for your heatsink on a i7 920. You can use far less than that and be stable. I'm at 3.6(CO stepping) with about 1.1v, try that and run prime again. You can always add small increases if you need more, but 1.1 is a good place to start for that frequency.