Hey guys, I got a little temp/cpu fan speed concern I'm wondering if you can help me with.

First off, I'm pushing an intel P4 2.4. I'm presently running my cpu fan, vcard fan, power supply fan, 2 rear outtake fans, and 1 side intake fan. (presently no front intake fan, but planning on getting one).
Idle CPU temp is around 47oc, mboard temp around 31oc. CPU fan runs at a constant 4000 or so when idle.

First off, several months back I took my computer in to get serviced. Guy told me that my cpu temp was awesome, and was cooler than the air temp inside the case. Now, it runs at the temp I mentioned for some reason. All my fans are running properly, but when I check my specs on asus PC probe, it shows my power fan and chassis fan running at 0, and flashing the warning that "Power fan below threshold".

Anyways, heres the deal. First off, if the heat sink is taken of the processor, does thermal gel need to be reapplied to it? Is my cpu fan running at an average speed? cause its louder than I'd like. And does anyone know why Asus pc probe isnt detecting my power and chassis fans? all my connections seem fine, and the fans appear to be running fine.

Help is appreciated!

Your problem is not about the fan, it's about the heatsink of the cpu. Here's my tip, buy a thin heatsink and leave the fan as it is. The thinner the heatsink, the faster it gets cooled.

About your Asus, i think you need to consult Asus about this.

"buy a thin heatsink"

Where do I go to get this?

Of course you have to find it yourself. There is another way, but it will spend most of your time.

I forgot to add. Intels' heatsink is thin, but not thin enough.

Is your CPU fan plugged into the motherboard where it says CPU fan?

You need an intake fan also. You have to have a way to pull cooler air into your case.

YO

It's almost impossible to overheat a P4...besides, your temps aren't bad

The only way your fan speeds will show up in probe is if they're plugged into the motherboard with the small 3-wire plug...2 wires are for power, the 3rd wire is the rpm sensor. If your fans are plugged directly into the power supply, you'll get no readings in probe

"Guy told me that my cpu temp was awesome, and was cooler than the air temp inside the case"

the guy is nuts

"The thinner the heatsink, the faster it gets cooled"

Not correct. The speed of cooling is proportional to 1) the thermal conductivity between the cpu an the fins, and 2) the thermal convection applied to the fins

Item 2 means you need a fan to move air up against the fins. Its exactly like using a hose to wash your car. The stronger the flow the more easily the bad stuff gets transferred away.

Item 1 means you need A) a path from the cpu to the fins that has little thermal resistance, which is achieved by using thermal compound and using a well-made sink made of copper or aluminum or both, and B) a sink with enough mass to conduct the heat in question.

A thin sink violates point 1B.

hmm, I'll check the connectors going into the mboard and make sure they arent going into the power supply. If the mboard isnt detecting the power and chassis fans, is it going to speed up my cpu fan speed to compensate, or is that speed completely determined by the thermal sensor?

As far as cooling goes, I'm going to check the thermal gel on the cpu, and I picked up an intake fan for the front to get more cooler in. Hopefully this'll work out.

Thanks for the input guys.

Ok, now I'm confused. I checked my thermal gel, and everything there seems cool. Then I went out and got another fan so I have air intake in the front. I checked the fan to make sure its sucking air into the computer, and yet now my cpu temp hovers around 49oc and my mboard temp is up from 32oc to around 35oc. It just keeps getting worse......

Ideas? help? thanks

if your mobo is reading the cpu thermal diode (inside the cpu) then your temp is normal

http://mbm.livewiredev.com/mobolist.html

You checked the thermal material? How did you do that...take the heatsink off the CPU & look? When you do that, you should completely remove the old material & replace it with a fresh layer...

What other fans do you have? You should have a front intake (which you have)...plus the power supply fan (exhaust), & usually another exhaust fan just beneath the power supply.

Have you updated your BIOS lately?

Presently I have the power supply fan, 2 rear exhaust fans, cpu fan, side case fan, front intake fan.

When I checked the thermal gel I took the heatstink off the processor. The layer on the processor was almost non-existant, so I removed the gel on the heatstink and simply applied a proper layer to the processor (still very thin). Should I go back, completely remove all the gel from both processor and heatstink, and reapply?

The first time I ever checked my processor temperature was 2 mboards ago (thanks to my luck with faulty ones) and back then my idle processor temp read (using Asus PC probe) at 42oc. Note that was with exact same processor. Been in the same apartment too, same room temp. I DID add a second hard drive. Would that serve to raise the case temp and affect processor/mboard temps? Also, after removing the cpu fan and putting it back on, its a bit quieter. Running at same speed (bout 4000). Havent updated bios in a while, will do that.

Any other thoughts?

did you check the link above to see if your mobo is reporting a cpu thermal diode temp?

"I DID add a second hard drive. Would that serve to raise the case temp and affect processor/mboard temps?"

Yes. My machine runs 1c-2c hotter with 1 7200rpm drive in it than with 1 5400rmpm drive. Two 7200rpm drives would make a difference, though it depends on airflow.

Machines in apartments have higher temps than machines in homes which have higher temps than machines outdoors. Entropy needs room.

Your temps are fine and if you drop the subject everything will be fine. Few people can do so, me included, but its worth pointing out.

1) Almost all P4 boards report CPU temp from diode. I have not encountered one that is not.
2) Your temp is not at all bad.
3) Intel Stock HSF sold with below 3Ghz retail pack is all alumimum and never goes over 4000 RPM.....the copper base one will.

Lastly, you never mentioned what Asus motherboard you have. Find a reputable place to service your PC, and don't expect an eighteen year-old kid with "cyber-guru" T-shirt take your money.

Hey johnoh!, I told him to replace the heatsink because he has a powerful fan to begin with. Did you study Physics?. It states that warm molecules tend to move to cool molecules. Here's the explanation, if the heatsink is thick, there is a high possibility that heat stays in to the heatsink for long, but if the heatsink is thin, there is less possibility that heat stays in the heatsink.

Note: study Physics.