I originally installed an i5-750 into an ASUS P7P55D mobo with stock Intel fan and experienced high temps at idle of 51-52 degrees with mild overclock to 3.2GHz (BCLK 160).
I was worried about these temps so I ended up overspending my budget and picked up a Noctua NH-U12P SE2 heatsink/fan combo. The i5 with Noctua only slightly decreased temps by 1-2 degrees at 50-51 degrees at idle. All temp readings were taken from the P7P55D mobo's BIOS.
The system specs are as follows:
- 64GB SSD drive
- Seasonic M12D 850W power supply
- Asus P7P55D mobo
- Noctua NH-U12P SE2 CPU fan (dual fans set with no resistors at max speed)
- Sapphire 5770 Vapor-X
- Lancool K7 Case
- 2 intake fans (Nexus D12SL-12) on front of case in stock location
- 1 outtake fan (Nexus D12SL-12) on back of case in stock location
The two NH-U12P CPU fans are oriented to conincide with the intake/outtake direction from front to back. I triple checked the fan orientation of each fan to ensure it was blowing from the front to the back in the case.
Fan air flow as follows: (all in one direction, CPU fans are aligned in parallel with the the case fans)
airflow in---->front of case ---->2 front case fans----->noctua fan1--->heatsink--->noctua fan2---->exit case fan---> airflow out
CPU Voltage 1.2
ATI Catalyst software reports temp GPU temp 38
P7P55D BIOS reports mobo temp 26-27
P7P55D BIOS reports CPU temp 50-51
- I've read as much as I could on these forums and tried different CPU fan orientations but no difference.
- Tested by opening the case wide open but no difference.
*** I've tried reseatting the CPU heatsink but no difference. ***
Tried different methods of applying the thermal paste such as the rice method, multi-spot method, 3 lines, X method, razor blade application, etc. I tried just about 10 different thermal paste patterns but no difference. I also tried Actic Silver 5 paste in addition to the Noctua included paste but no difference.
I've read that the normal temps with the Noctua at high speed (no low noise connectors) are in the low to mid 30's, not 50's as I'm experiencing.
I'm out of ideas.
Any ideas as to why the temperatures read so high at idle would be much appreciated!
My i5 750 idle temps are about 30C with a Zalman CNPS10X Extreme, which isn't supposed to be as good as yours.
Have you compared Load temps running Prime95 or Intel Burn Test? That should be a more telling story for certain.
Secondly, you should really look in your BIOS and enable C1E, EIST, and C States. These are power saving features which will definitely help in dropping temps. Note that on these ASUS mobos they tend to have a hum/buzz/squeel sound at idle with C states. I found that setting the C State limit to C3 (as opposed to C6) got rid of it. Others reported C1E fixed it... and some people don't have the noise at all.
Anyway, check if those features are enabled and let me/us know.
EDIT: I forgot, but to get the 160 bclk did you do it manually or with XMP? I was commenting on a different thread where XMP was causing a huge temp increase. I recommend setting your OC manually. My ASUS P7P55D Pro allows me to set a 160 bclk without even changing the voltages off of AUTO (it will auto increase them a bit). I found that I only had to manually increase voltages at around 165 or 170 bclk as I guess the efficiency of the CPU goes downhill so it needs excessive volts at that point.