Sizzling sound coming from PSU

[Rua]

For a while now I've been having random freezes at times while using my computer (Linux Mint 11). I wasn't sure why but I suspected the power supply. More recently I would occasionally hear a kind of sizzling or arcing sound come from the PSU when I turn on the computer, but only the first time I turned it on that day. That was really the last straw so I got a replacement PSU with a higher power rating.

But I just installed it now, and when I turned the switch on the back of the new PSU, I heard the same sizzling sound coming from it, without even turning the computer on. I also noticed the lights in my room flickering during that sound. This has me quite scared because I don't know what's causing this, and the rest of the hardware is only six months old. Can anyone help me please?

[Myself]

My thoughts as they occur.

It could just be the high frequency sound of the switching electronics at work.
Switched-mode power supply
https://en.wikipedia.org/wiki/Switched-mode_power_supply

or a 'humming' transformer (probably not) ,

or... ... worst case - it could be moisture getting in through damaged shellac coating on the transformer which would give sizzling and arcing sounds.

But weird that it's drawing so much power to dim the lights. Sounds more like some sort of short-circuit. I've had this in the past with some lower grade motherboards and it was usually faulty capacitor/s in the voltage regulator circuit. Capacitors often give warning with a sizzling, hissing, 'singing' sound. You would also hear this coming through your speakers/headphones when listening to audio/video.

Oh! I have had power regulator chips blow-up with big bang, massive flash, and stinking smoke but they never gave any warning.

[Rua]

What's confusing me right now is that this sound has now come from both the old and the new supply. The sizzling sound does seem like AC arcing... like regular sparking at 50 Hz (but I am not an electrician, I just watch videos!). So it seems that something is shorting out, but I have no idea why this would happen to both power supplies. I will try to record a video of it with my camera if it happens tomorrow again when I turn it on (it seems to only happen then, not later in the day when it's been on for a while). I've also thought of unscrewing the supply and holding it away from the case so I can pinpoint the sound better by ear. It may well be the motherboard but so far I haven't seen any sparks on it, just the sound.

In case it helps... the old power supply is a CoolerMaster RS-380-PCAP (380 W) and the new one is an OCZ ModXStream Pro 500 W. The CPU is an AMD Phenom II X4 840, the graphics is a Radeon HD 5770, the motherboard is an MSI 770-C45.

[AlbertP]

Probably the cable from the PSU to the net is damaged? Or there's a short-circuit somewhere else? You can try disconnecting components that you don't need from the power to be sure that they're not causing this fault.

Oh no, now my computer also randomly turned off... I had my feet on the power cord

[Rua]

The new PSU came with a replacement cable so I am using that now. Maybe the sound is coming from the contacts there but to me it seems that it is firmly plugged in. I'll try your suggestion though, I'll try unplugging the graphics and see if anything happens then.

[Oscar799]

Moved here by moderator

[Snowfall]

Perhaps you've solved this already, but I'd like to suggest an alternative cause to your problem...

Are you sure the problem is caused by your hardware? I've heard that high-frequency sound you are describing too, it is normal for most modern PSUs and it can get pretty loud in cheaper PSUs (due to low-quality or poorly assembled transformers).

I've also heard it intensify to an alarming level (sounds sort of like a short-circuit spark) when power levels are fluctuating in the grid... lights would also flicker during these external power fluctuations. This is also normal, since the PSU is no longer operating within designed input parameters and is struggling to cope.

Worst case scenario, if the fluctuations get worse and something does eventually cause a short-circuit, the inner fuse of the PSU will burn, or your house/apartment fuses will trigger.

If the lights have been flickering even when you've kept the PC off, then I'd check with a technician because it's definitely a grid problem in that case. Also check if some other device that is tied into the grid is causing these issues.

If that is not the case, then indeed something inside your PC would be the culprit. Make sure the motherboard or any loose contacts from cables are not touching the case or, as AlbertP suggested, sequentially remove components from your PC to identify if any of these are faulty and causing problems for your PSU.

Good luck!

[Rua]

I've never seen the lights flicker except that one time while the sound was there. Our power has always been very stable so I don't think it's that.

I tried to make a video recording of it this morning when I turned my computer on, but of course nothing happened. Mint did stop booting half-way through, though, but started fine the second time.

[Sioux]

Here's what I would recommend ...

(1) If you're using any power-strips, replace them if possible. They wear out eventually.

(2) Before turning on the computer, turn on some lights in the same room and go over to the breaker box. If your breakers aren't labled, you'll have to go reset them one by one until you (or somebody else) tells you that the lights went off in that room. Once you've isolated the breaker, look at it. It should tell you how many AMPs (i.e. 15, 20, or 30) its good for before it trips. Consider asking an electrician to replace that breaker.

(3) Homes and apartments built around WWII or prior are increasingly becoming inefficient when it comes to electricity. Often times, the wiring has degraded so much that the entire place is no longer grounded, and if you ever intended on cashing in on the guarantees of some surge protectors and UPS units, they explicitly state grounding is a must. And when your house/apartment isn't well grounded, your electronics become more susceptible to what is known as "dirty power" ...

http://www.electriciantalk.com/f2/what- ... wer-16131/

... and they can literally eat computer PSUs alive - even the best top of the line switching PSUs from Seasonic and FSP. Keep in mind that it's normal for switching PSUs to make a sound every once in a while like just earned a free credit on a pinball machine. Just not as loud. A faint "KLOCK" sound is perfectly normal. But if you hear it more often than not, could be a sign the PSU is taxing itself. Of course, its expensive to have one's house or apartment rewired (or getting the land lord/superintendent to do it), and that's where a decent UPS comes in. Even the cheapest ones on the market that'll maybe give you 30 mins to an hour of power if a storm or accident takes out a uility pole have good tolerance for dirty power and automatically condition the output signal with a clean sine wave that computer PSUs love. Plus, its an overall good idea since that last thing you wanna end up doing is re-installing your OS after a sudden power loss boarked your system. So a UPS gives you a good grace period for getting documents saved and everything shut down normally.

(4) Easiest one that doesn't cost spending money you may not have: Re-locate the computer! Lights shouldn't flicker or go dim when you power up a computer unless there's a short somewhere in the in-house wiring or the breaker to that room is being stressed and about to trip. Sadly, most homes and apartments will slog the utility room where the washer and drier is on a 30+ AMP breaker ... and leave the living room, kitchen, and bedrooms on 15 AMPs or less; 20 AMPs if your lucky. My kitchen is on a 20 AMP -- can't run a coffee pot, the toaster, or the microwave at the same time. Good thing the stove is gas!

[Rua]

1) The one I am using is still fairly new, so I don't think that's really an issue but I can always try.

2) The highest allowed rating here is 16 A so I think it's that.

3) None of the sockets in this house have any grounding except in the kitchen, and that's fairly normal for older houses. I think modern houses are made with grounding everywhere though. We don't have utility poles here and we almost never lose power. In all my life I can only remember two power outages in this house...

4) I'm afraid I can't relocate, I only have this room to put it in.

[AlbertP]

2) The highest allowed rating here is 16 A so I think it's that.

You're probably in an area with 230V tension. Then you need only half of the A that the same equipment on 115V requires. 30 A breakers are probably available in the Americas but in Europe 16A is the norm.