I was getting ready to try overclocking the i7-920 rig that I put together in February, until I decided to run Prime95 and monitor my temps for a while, just to see where I was starting out. The results have me... surprised, to say the least. I'm running an i7-920 @ 2.66 (d0 stepping), Hyper 212+, ASUS P6X58D, in a HAF-922. I used AS5 thermal paste. When I did the build back in February, the first thing I did was run Prime95 for 24 hours, standard stress test for a new rig. I don't have my screenshots anymore, but my load temps were generally in the 50 degree range, plus or minus a degree or two.
Today, I started up CoreTemp and RealTemp, and noticed that my idle speeds were hovering around 36-38 degrees. That seemed high, considering I'm still at stock speeds, so I started up Prime95, and within seconds all four cores had jumped to 58-60 degrees. During 15 minutes of testing, they slowly climbed to 67, 64, 61, and 61 degrees for Cores 1-4, respectively. These seem like the sort of temps I should be getting with a stock cooler, not an aftermarket HSF, especially one as well-regarded as the Hyper 212+. Obviously it isn't the *best* cooler on the market, but it's supposed to be able to hold its own against the heavy hitters.
Do any of you guys have suggestions before I start disassembling my rig to re-apply thermal paste, or buy a more powerful cooler? These temps are unacceptable, and I can't even consider an overclock until I figure out what's wrong - unfortunately, though, I'm not really sure where to start, given that my temps were much more reasonable right after my build. If anyone has ideas, I'd love to hear them.
Reapply the thermal paste. Just don't use too much. I know it's not the case, the HAF 922 has decent airflow, and the Hyper 212+ is no cooling slouch either. Also, make sure your HSF is properly seated.
You should consider doing some lapping on the HS and CPU, as sometimes they aren't very flat. Mine was particularily bad, it was going into high 70s right away but now I'm only going as high as 61C as my highest core, the rest around 55/58C.
Agreed - best method for applying TIM to the CM Hyper 212+ is shown at that benchmarkreviews site. You need to fill in the gaps between the copper heat pipes, on the underside of the heatsink.
Nothing wrong with AS5 Thermal Paste - it works well.
Your temps were OK back in February, but have gotten worse over time. Something has changed. Make sure your case air intakes aren't plugged up with dust. Likewise, blow dust off of CPU heatsink and mobo with compressed air. Dust is a great insulator.
You could add a cheap second 120mm fan to the CM Hyper 212+ to give it a push/pull configuration, but that still doesn't get to the root of your current problem, because you were good in February, and two months later it's not good.
If you O/C your i7 920 but worry about temps, just go as high as you can using the stock Vcore voltage. Lots of folks hit 3.6 on stock voltage, and it doesn't add a lot of heat to your CPU (extra volts = extra heat).
When you torque down your heatsink, do it a little bit at time on each screw, so you are more-or-less applying the pressure evenly during the torque-down.
Temps below 70 Celsius at full load are fine.
If you turn off hyperthreading, your load temps will go down if you were testing with all 8 (virtual) cores running full tilt.