Strange noise from my PSU

I've got a about 2 1/2 years old 235 watt PSU in my computer. Lately it has a strange noise inside it, almost like the fan is hitting a wire or something, like a rattling noise. After a while the sound stops and my computer sounds as usual. It doesn't occur all the time, and sometimes it happens while the computer has been switched on for a while.
I checked the PSU by removing it from my computer and see with a flashlight what exactly happens, but I couldn't see a thing. I am a little afraid to open it completely to have a clearer view, because maybe I will get 220 volt shock when I accidently touch something.
My computer is working fine, and all the fans are rotating as they should do (inclucing the PSU). Is it harmful to continue to work on my computer or can I damage any components in my computer (except for the PSU) if I continue?

OK, other question. Are all the PSU's the same? The PSU which is inside now, is from Packard Bell and it is a normal ATX. Can I replace it safely with another PSU, without worrying about not fitting parts?

Thanks in advance.
Well, what parts are there to fit? There are the power connectors for your motherboard, make sure to check what kind those are, because as far as I know, some mobos have different ones, while the harddisk and the cD drives, as well as the floppy drive connectors, are all standard. Sure you can get another power supply. As for what is wrong with it, you won't get a shock if you unplug it and then open it...I hope :p if there is a rattling noise, what I can think of is that maybe one of the fans is loose and is rattling...
Yeah, I thought about that too, but I was not sure and if someone has had very bad experiences with it (perhaps as a computer reseller), then I would replace it immediately. But I think I better wait untill I've got some time (and money) to do it.
Thanks anyway, Nick M.


i had a similar problem a while back, i just opened the psu up, and regreased the fan inside (you need to move the sticker and the little cap while you put the grease in. if you're careful, u wont get grease where the sticker was so it can go back on). alternatively, you can replace the fan... but you'll either need a soldering iron (or you can cut and join the wires up inside).

good luck.


I am a computer reseller and I do not recommend opening up the power supply and playing around unless you have some skills in that area.. PSU's really aren't that expensive so hang in there and if this one dies on you pop out to a clone dealer and pick up another one.. since yours is a Packard Bell the PSU may be of a different "form factor" (design) and a standard PSU may not fit properly.. if n it dies on you pull it out and take it to a clone dealer to see if they have one you can replace it with.. if not you may need to try and find a spare PB PSU somewhere which may be quite tricky..
jonocainuk: Good point there, greasing the fan. I might gonna try it.

RobbieSan: Well, I did open it and luckily nothing (bad) happened. I got a vacumcleaner and I vacumed it (with a gentle brush and minimal suction), but that still did not work.
A day later (3rd Sept.) I installed a harddrive bay and ever since, no 'strange sound' emerged from my PSU. Even not today, while my computer has been switched on for 8 hours straight.


I can see your point about opening up the PSU RobbieSan, but I didnt know anything about PSUs when I first re-greased a psu fan and I was able to open it up, take the fan out and sort that out without having to touch or bother anything else inside.

You should still be careful when opening the PSU though. Make sure it isnt plugged into anything (no system devices or mains plug - sparks would fly - DOH!!)


It probably wouldn't be a bad idea to replace the fan in the powersupply, and you can do that without soldering. Get a case fan at a computer supply store, 80mm I believe, when you take the old one out generally there will be a red and black wire attached to the board in the psu, clip those as close to the board as you can, I've used fingernail clippers to do this or a pair of needle-nose pliers and pull them out. When you put the new fan in you will notice two arrows for positioning, one should point up and the other away from the psu for air output. The bundle of wires coming out of the psu have like a plastic gasket that holds them together, you should be able to pull that out of the casing and run the wires from the case fan out with the rest, just remember you'll need to plug that one in. The power plug on the fan should plug into one of the plugs from your psu, or if you have a spare fan plugin on your motherboard near the psu you could get a case fan with a 3-pin connector. I've changed several fans over the years and never had a problem, just don't touch anything inside the psu you don't need to and you'll be fine.
Hmmm. If that would extend the lifetime from my PSU for a year or so, it's a good idea. I'll go through all the options in the next few days and I keep you informed.
Any other ideas? Post them here!


It is really unadvisable to open the PSU, due to the fact that a slight change to the voltage to the MB could cause un-repairable damage. Does sound like the bearings are on the way out though, so if you do open it up make sure that it has been off for a while as a PSU stores power and it takes a while for it to disipate. I would advise bearing with the bearing until you can purchase a new PSU
You can buy a Case and PSU for about £45.
Hmm. I'll go to the computermarket tomorrow with my PSU and see what it'll cost. Or I could e-mail Packard Bell, maybe they could replace it for a small fee. It's worth trying it. Not shooting is always missed, goes the saying here in Holland, guess I'll just have to 'shoot'.