I got a new pc from work, and I'm trying to think of way's to silence it. Actually, it's not a new computer, rather an old P3 600 compaq small factor pc. The only fan in the case is the one on the powersupply which is a bit loud. The cpu is passivly cooled, and get's pretty warm under load. (I'd like to change that as I can't really fold as is)



Here you can see an image of the case. The yellow part is the fan on the psu, the red thing indicates where the processor is. On top of the cpu is a tray that turns up. The tray holds the hardisks and cd-rom, and there is only a really small gap between it and the heatsink of the processor. The blue cross on the rear end seems like a logical place for a fan, but the motherboard hosts all the pci slots just there, so I can't really put a fan there either.

Under load the processor temps immediatly jump to over 60, and I have'nt had the nerves to see how high they could end up climing to... Is this a lost cause, or do you think something could be done about it?

One thought - try and optimise the original design.

Where (if anywhere) are the inlets? Can you make/enlarge any inlets at the front left? (So air comes in the front, across the CPU, and out the psu.) Also the 'usual' hacks on the psu - remove all 'more tin than air' grills, replace the fan (what size is it?). Tidy all cables ...

Actually if it is quite old the psu could probably do with a service (using an air gun!) - it could have more dust than air in it!

I could try cleaning out the psu while I change the fan for a panaflo. As mentioned, the psu fan is the only one there is. There also is not really any air inlets... I could have a look if I could make a hole on the front left, I guess that is actually the most logical place for one.

The thing that bothers me the most is that I can't fit a fan anywhere close to the cpu even if I'd want to...

Shouldn't be such a big issue. The total power usage is probably around 50W so you dont need masses of airflow. An 80mm L1A in the psu @ 12V should shift around 15cfm (allowing for some static pressure) which is plenty. The trick would be to get most of that airflow going across the CPU (to keep it cool) as well as under the HDD (ditto). But there is no pressing need for an intake fan - just intake vents that are unobstructed and preferably similar total dimension to an 80mm diameter hole (to reduce static pressure).

I have a SparcStation 20 that was running extremely warm. I finally found out that the PSU was so covered with dust that hardley any air was passing through. A good cleaning helped out a lot.

I also have a Dell Precision Workstation 410 which has a hard drive rack in the front. I had 4 SCSI drives in there and they started overheating. The rear exhaust fan was temp controlled and never seemed to spin up enough. Plus there were extra holes for air to get into the case. Since the HDs took up so much room there wasn't much room for air to get in that way, so it took the easy way in. After replacing the fan with a Panaflo 92mm M1A and covering the extra intake holes, the drives stay extremely cool.

So, as Dukla mentioned, make sure you have some vent holes near the CPU and also make sure you block any other places that air might get in. This will ensure that the air coming in passes across the CPU.

Is it Socket 370 or Slot-1?

I'd make a hole to the left side, and duct it through the CPU HS. Maybe no extra fans needed. That is, if it's a Socket type...

Cheers,

Jan