I bought a very cheap power supply last year when my enermax one gave out. Last night my pc was making an ear-piercing squealing noise, a very high-pitched one. I reckon it's because of the cheap PSU. Any electronics experts here who could give me any other parts to consider doubting/replacing... ie is there anything else inside a PC that could feasibly do that?

BTW it seems to be ok today thank goodness.

Check PSU, fans and hard drives. Those are the ones that usually makes high pitch sound. Stick your head inside the case if you have to, but be careful not to get electrocuted.

I was wondering if it could be a hard drive. I have 2 36Gb raptors in there and as they both run at 10kRPM I can easily believe that if a ball bearing (or whatever they use in HDDs) gave out then there would be an awful racket.

As regards the PSU it has a huge fan in there, 13cm I think, but it has never worked. It only cost me £20 which is dirt cheap for a 600W power supply and I know you get what you pay for but I had just finished uni at the time and had no job, but I do now, so I had to cheap-out on a PSU. I would find it easy to believe that over time it would slowly die due to no self-cooling but the PC has lots of fans in it which should help with that.

My case is an EZ Cool Alpine which is almost completely punched-out with holes so the whole machine is kept cool all of the time. There are 2 zalman 80mm fans intaking on the side, an akasa 120mm fan exhausting at the rear and a non-branded 80mm fan exhausting at the top (to get rid of optical drive heat).

It briefly squealed a few mins ago but it seems to have stopped now. The pitch is so high I can't make out where it's coming from :-(

I think I'll be getting a brand new PC sometime in the future anyhow, so I'll transplant HDDs/opticals from this system and let my brother have the mobo/CPU/RAM from here.

It's not easy to narrow down where the sounds is coming from when you hear from inside the pc. Well, keep your ears open and when the next squeal, try locating exactly where it's coming from.

Do you have any tiny fans on your motherboard like the ones in north and south bridge chips? Those tiny fans spins at 5000rpm and can easily wear out it's bearing, which I had the same problem before.

just wona add my 10c check to make shoure nothing is tuching your fans i had a ciggie paper get sucked inside my case and it was tuching the northbrige fan mad a realy high pitched sound

Nope, it's a clean case and the wires are all kept in line, so to speak. Well it's no longer an issue but if it starts again then I'll be getting a new PSU, it's not worth killing a decent-ish PC for the sake of a PSU.

if the fan for the psu didn't ever work then its less likely thats what is making the noise. I would focus on the cpu fan or the raptors as the more likely culprits.

clearly some experience needs to be shed on this issue. one word = fire.

if your PSU is 'squealing' its because it's capacitors are doing it because they are blown or corroding significantly, or electricity is arcing on the inside of the PSU. neither is good. if left untreated, you could be looking at something as small as a new PSU, or you could have to replace most components in the PC if they get blown out by a short in the PSU, or your PC could just ignite into flames from electrical arcs and dust and burn down your house...

sounds far-fetched doesn't it? yes, well, it's not. so toss your cheap chinese power supply and go spend your $20-30 on a new one from the store. my experience comes with advice -- don't wait until you start to hear the noise again, replace it now.

on a side note, if you're not sure it was the PSU making the noise, inspect your mobo's capacitors as well. if they are not flat on top, bulging out, showing signs of 'leaking' or corrosion/oxidation, then they are bad and potential candidates for your strange noise. check them all -- if they look fine, its your PSU.

I would get rid of that $20 "600 watt" PSU befor it takes out everything it is connected to!

Well said and VERY true. And, even if catastrophic failure does not occur, ripple current is likely VERY bad on cheap unit with squealing caps. Ripple is AC bleeding thru to your PC components and will damage them over time. GPUs and HDs are especially sensitive to this.

Most likely, you are damaging your PC components if your caps are squealing. It may be slow like a cancer or it may just blow up and take some gear with it.

My wife used to give me the same problem. A few smacks fixed the issue.

PS. Just Joking. I would never smack my wife. A donkey punch is much more effective.

Check the CPU fan, chipset fan, power supply fan, video card fan and casing fans.

Most of the time you can stop those fan with just your bare finger...I don't recommended it, unless you know how to put your finger right in the middle of the fan top spindle part. On the other hand, you could wear a glove then, you can stop them easily. Good luck.

I'm betting the psu is bad,I just had a redundant set up do the same thing...IMO replace it so you don't encounter other problems...If you have the time tell us what the rails are reading(under load and without)gl .

I've found the source of the whine, it's the fan exhausting heat out throught the top of my case. All of my other fans are decent branded (zalman/akasa) units, this one came for 'free' with the case and it seems to be the source of annoyance.

I'll get a new PSU anytime soon anyhow. I appreciate all the advice very much.

Glad to hear it,but putting such a stress on your parts from a inferrior psu is not worth the gamble IMO.Personally I would wait to use it until I got the proper equipment,but at least check the rails under load to make sure,gl .