Cooling the Pentium D

j0hn1215 · Rated PG Joined: 04 Aug 2006 Posts: 1

I am currently building my first DYI computer with a Pentium D 840 underclocked to 2.8GHz, but my bios is still reading an idle speed of 52C.

I'm read this forum over and over trying different things to cool my CPU (originally it was idling at around 62C) but I can't bring it any lower.

I have two 120mm (70CFM) case fans (although my case is open so those shouldn't matter much), a Scythe KATANA Cu HSF, and have applied my Artic Silver 5 thermal compund several times to make sure it's as thin as humanly possible. I also have nothing else hooked up (besides RAM) to prevent any heating from any other components.

I mean it's underclocked 13% of its maximum value and it's still running far too hot.

Please help! Any assistance would be greatly appreciated.

Blue|Fusion · Posted: Sat, 05 Aug 2006 01:51:37 Post Subject:

Don't go based off of the BIOS temp. It's more accurate to access your motherboard's monitoring chip with a program directly and not go off your BIOS temps.

If the BIOS says it's running at 52C, it's probably closer to 45-47C (atleast that's how mine is).

I'm actually in the process of overclocking and undervolting my rig a little bit this evening. I've upped the FSB to 225MHz, the processor is now at 3.6GHz @ 1.285V and the RAM at 4-3-3-8 (from 4-4-4-12) timing @ 900MHz (from 800MHz) @ 2.0V (rated for 2.1V).

The decrease in voltage on the CPU gave me about a 2C drop in temperature at idle and under load. To make sure the stability is still there, I'm running 2 instances of Prime95 (one on each CPU core) overnight. It's been about 3 hours and no warnings/errors so far.

If you feel up for it, you should try it out yourself to take a few more degrees off, but be sure to test it for stability!

jaykub7 · Rated PG Joined: 04 Jun 2007 Posts: 1

This may sound like a newbie question to some of you, but believe it or not, I have been building computers since the 386 time period. I have just never worried about cpu temperatures before.

I am running the following
Intel Pentium D 945 (Presler) 3.4 Ghz CPU
1Gig Ram
ATI X1300 AGP Video Card
Western Digital 120gig HD

What I am wondering is this, I notice in both the BIOS and through Speedfan I am getting two seperate temperatures, I get a Core Temperature and a System Temperature. I looked at the Pentium D 945 Specs, and it gives me the following:

Thermal Specification: 63.4°C

What I am unsure about is which of the two readings I should be using to gauge this?

If anyone can answer this question I would grealty apprecaite it.

Jacob J. Odea

**Jason** · Posted: Mon, 04 Jun 2007 18:49:48 Post Subject:

Hi... Welcome! You want the core temperature. System temperature is another probe located on the motherboard that can be located in different areas depending on the model.

**Modulok** · Posted: Mon, 04 Jun 2007 19:53:19 Post Subject:

either way, anything above 55c is high if you ask me

Blue|Fusion · Posted: Mon, 04 Jun 2007 20:17:05 Post Subject:

Take into account the Pentium D's suck temperature-wise anyway. My 840 idles at 44C with a 33C ambient temp. When working both cores at 100% the temp can climb up to 65C or more. It may shave away life off of the chip, but it should still last a good long while - longer than the purposes I need it for.

**~*77*~** · Posted: Thu, 07 Jun 2007 22:02:59 Post Subject:

I was just looking at old receipts and see I paid $326 for my first D840 processor! Jebus, I didn't know I ever spent that much on one CPU.

Crazy