View Full Version : PSU Cooling Fan

08-10-2001, 01:32 PM
Just reading an article on cooling in this months PCWorld, I've lately noticed that the cooling fan in my power supply unit isn't running as happily as it once did. The PC is on 24/7, and I often hear the fan surging (high-low-high speed) or cutting out altogether for periods of time. I'm not terribly worried as its been doing it for a few weeks without any problems, and the side of the case is permanently removed, but is it possible to replace the cooling fan inside the PSU without having to buy a new unit?

08-10-2001, 01:58 PM
yes, easy enough to do. most but not all power supplys run 80mm fans. you can simply buy a replacement, pull the old one out and plug the new one in. some high speed fans don't have plugs do a little soldering is required.

varable speed fans can be a little tricky try to get one that draws the same amount of current.

don't forget to UNPLUG IT FROM THE MAINS. if in doubt get a pro to do, getting electrocuted is no fun.

with a good cooling system leave the covers on as this will quieten down the noise and improve cooling.

08-10-2001, 02:13 PM
Yes, be very careful. As well as the AC mains, the main storage capacitors have 320V and some microfarads. If you manage to touch that, you might be lucky and just get a severe belt. They *should* discharge when powered down, but relying on that could be fatal.

08-10-2001, 04:09 PM
Bearing in mind Grahams safety warnings, it is possible to pull a fan apart and clean out the sleeve bearings, then re-oil with a drop of '3in1' thin oil. There are 2 things to watch out for. There is often a very tiny flimsy circlip to remove, underneath the self-adhesive label and blanking plug. The other thing is that the stator winding may come adrift and the wire is thin, like 50 swg.

A new label or cover needs to be stuck back on to prevent the little plug falling out, or dust getting in.

Even if you wreck things, nothing is lost, as it wasnt going properly anyway, and you may save yourself $50 or so!

08-10-2001, 06:50 PM
Before you pull it apart, have a check on the PSU, or prehaps the makers website, to see if it uses a temperature comptrolled fan.

My system has one and its speed varies quite a bit (although never stops).

But if its a new problem then its probably dieing.

I had the bearings (I think) go on one of mine and it viabrated so much the whole PSU would slide around my bench.