Issue 76 - Media Rig and Overclock to 3.8Ghz running HOT!

[Creakychair]

Hi,

I've just completed the media rig build from issue 76, with a few changes to the spec. Namely the power supply is a better Corsair 650W Pro (in case of future GPU upgrades), and there's 2gb more Dominator RAM, but the same specced stuff and the rest of the PC is identical to the magazine article.

I've put it together as per the instructions, and it worked first time no problem at stock speeds.

So I went through the overclocking process, and that also worked fine.

But under load, the CPU cores are hitting 85 degrees in some cases. Which is apparently 15 degrees too hot.

Now I can hear you all screaming that the heat sink isn't seated correctly, but it's firmly in place and double checked!

So what could be causing it to get so hot? And what can I do about it?

All help and suggestions greatly appreciated.

[Lizard]

85C really is way too hot - I know you said you've checked the HSF mounting, but did you apply TIM, and have you checked that the fan on the HSF is spinning?

Also, it's worth looking in the BIOS to see whether the HSF fan is running at full speed, not in some 'super-quiet and rubbish cooling' mode.

[Creakychair]

Thanks for your help!

The paste was already on the sink when I got it. A Freezer Pro mk2. Just checked the BIOS settings. The fan is already set to respond to CPU temperatures. I have the option of setting it to respond to voltage instead, which I just tried to no avail.

[Lizard]

Okay, how about the the case fans, are they working?

Also, where have you got the PC, i.e. it will get hot if it's next to a radiator.

[Creakychair]

Nah it's nothing obvious like that. Not anywhere hot, and the fans are all working fine. The temp jumps straight up from an idle 49 degrees to 80-85 within 5 seconds of running a stress test with 100% load on all 4 cores.

[MaverickWill]

Is the HSF facing the right way in the case? That could mess temps up. Should be an arrow on the fan indicating airflow direction.

[Creakychair]

It's facing the same way as demonstrated in the magazine article. And it's working fine. Speeding up when under load.

I just can't understand why it's so much hotter than it should be! Any more ideas?

[MaverickWill]

I'd reapply TIM, if you've got some spare. The pre-applied stuff may not be making contact. If you're in the Sunderland/Newcastle area, I'm happy to take a mooch over and give you a hand (I'm a night owl, and I'm realy bored).

[Creakychair]

Very kind of you to offer. But I'm at the other end of the country in Devon. However, I will get some TIM tomorrow and do just that.

[MaverickWill]

I'm not that much of a night-owl. :P

The general forum consensus is for Arctic Silver 5, because it gets the job done, and isn't too flash/expensive.

[Carper]

i would of thought a 3.8ghz overclock was a little too much for that cpu fan.

[Creakychair]

Originally Posted by Carper

i would of thought a 3.8ghz overclock was a little too much for that cpu fan.

Not according to the mag!

Tried new silver paste, tried reorientating the fan to the other way, tried reapplying the whole heatsink assembly to the motherboard again. Everything, still no good.

Is it possible it's got more to do with the voltages?

[philheckler]

I've got roughly the same setup , but i'm only running mine at 3.3ghz at the moment , under prime stressing my temps are around 55c max - my case is an antec 900 though so cooling is great - pehaps your overdoing it a bit with the voltage ?


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