Overheating CPU

[Roark26]

About a year after I built this machine, I started having problems with overheating. ~15 minutes after I boot up my computer, it shuts itself off. Even if I just load windows and idle the computer it does this.

So I cleaned out the inside of the case and all the fans (the cpu fan was quite dusty), and applied a fresh coat of Arctic Silver 5, expecting this to fix the problem. It didn't. If I boot straight into the BIOS, without even loading windows, the temperature on the CPU slowly ticks up from room temperature (26C) to 70+ C. The CPU fan is running at about 1k RPM and there are two chassis fans as well.

CPU: Intel core 2 quad Q6600
MB: Asus P5N-E SLI
PSU: Antec 650W

The CPU fan is the stock one, not aftermarket, but had never had problems with it previously and still seems to run fine.

Is there anything I'm missing here?

[glc]

Most likely, one or more of the heatsink retaining pins has come loose or you didn't snap them all the way down. Remove the motherboard from the case and start from scratch - clean the CPU and heatsink, reapply compound, and snap all 4 pins FIRMLY down into the holes in the board, supporting the back of the board with your hand. It is strongly not advised to mount a socket 775 heatsink with the board installed in the case.

[Roark26]

Ok, I did an out-of-case build (since I was removing motherboard from case anyway). Cleaned up the cpu and the heatsink of all former compound, and reapplied. I then very carefully pinned down the heatsink (opposite pins first) and it is now very firmly and evenly seated. Booted into BIOS and watched my temperature tick up to around 61C. Definitely an improvement, but still quite high for an idle temp. I've got a new heatsink arriving from newegg on wednesday, so we'll see how much that helps. Any other ideas? Is it time for a new cpu?

[glc]

What happens if you turn the CPU fan speed control off in the bios, allowing the fan to run full speed?

[Slaander]

60c is what Q6600 normally run at, I used own one of those dang chip, in winter you don't even need to turn on your heater lol, I upgraded to 9550 chip and the temp is little better 52c but compare to q6600 that is alot lower.

[glc]

The last Q6600 system I built idled around 40c with the stock heatsink. Full load was still under 60.

[Slaander]

Originally Posted by glc The last Q6600 system I built idled around 40c with the stock heatsink. Full load was still under 60.

you talking about Stock speed? the system I got was with 5 hdd in raid 5

[glc]

Of course. I don't see anywhere where the original poster says that he is overclocking.

[Slaander]

there also 2 type chips of q6600, B3 and G0, the chip I got was B3

[mike.shine]

Check whether the thermal compound connects both the fan and the processor.
I also had the same problem, it was ok when i fixed the fan tightly.

[Roark26]

What happens if you turn the CPU fan speed control off in the bios, allowing the fan to run full speed?

Fan control is already disabled. 1100 rpm seems to be the fastest it wants to go.

I don't see anywhere where the original poster says that he is overclocking.

System is not overclocked

Check whether the thermal compound connects both the fan and the processor. I also had the same problem, it was ok when i fixed the fan tightly.

Fan is tightly fixed, was very careful about that the second time around.

[glc]

Something is not right - full speed on my fan is 2100 rpm.

[systempat]

1100 RPM is not a good speed for a CPU fan. Think I'd be looking at a replacement on the fan if you want to tinker with it, or a new heatsink and fan.

Oh I see you have one on order. Hope it helps.

[glc]

If I enable fan control, it idles at 900 rpm, but it does increase under load.

[Roark26]

Yea, seems to have been a lousy fan.

The new heatsink fan runs at 2600 rpm when control is disabled. Idle temps around 39-40C. Thanks for all the help guys!

[systempat]

Originally Posted by glc If I enable fan control, it idles at 900 rpm, but it does increase under load.

Right. Well if the CPU is at 60C and the fan is at 1100 RPM, then something is not working. What size is the fan on the stock Intel HSF for a Q6600? If it's an 80 or a 90 it should spin up to like 2800-3000 under load.