Power Supply Whine, Not fans, Safe? Fixable?

[dmfree88]

I have a power supply on a dell xps 600 thats whining even when powered down. it gets louder (or quieter sometimes) when on or under a load (basically just sounds like it speeds up sometimes fast enough not to sound so bad). I am probably going to replace the power supply soon (its proprietary and a pain) , but I have heard that this is possibly just a coil whine and can sometimes be simply fixed with some decent glue. And that coil whining doesnt necessarely mean theres a malfunction (atleast not a major one). I recently posted about replacing this and still hope to but I was just wondering if its possibly rebuildable? the fans both seem to be working fine. the whine continues when shutoff but if i pull the power plug it comes to a stop. then if i plug it back in it starts back up again (even if the computers off). It seems to go away after i leave it overnight but comes back when its on for a couple minutes.

Should i dismantle and try to repair? Is it something thats just annoying that wont cause a problem? Just wondering whether its failing and if it is, will it damage my computer to let it fail? I imagine thats always a possibility atleast with hard drive damage if its reading/writing during failure. But asside from that is my power supply gonna catch fire? explode? melt my mobo? should i not use it till i get another power supply and fix it? or like i said is it rebuildable so i can fix it? just wondering if anyone has had a similar issue and if its just a simple whine thats not hurting anything. hopefully i have it replaced soon but knowing i wont hurt anything makes me feel better about it..

any suggestions/comments greatly appreciated, thanks!

 

[InvalidError]

Is the whining new?

Since the noise is there while the PSU is soft-off, this means the noise is coming from (or at least related to) the 5VSB regulator.

If it has been whining ever since you got it, the 5VSB regulator could simply be designed to operate within the audible range in which case there isn't much you can do to about it. This would be quite likely if the 5VSB regulator is a flyback type where low load on the 5VSB line could cause it to pulse irregularly. You can easily test that by checking whether or not wiring a 10ohms 3W resistor to the 5VSB line significantly changes the noise's pitch. If you still have 5V and the noise is either gone or much higher-pitched, your 5VSB whine is simply because the rail is under-loaded.

If the whining is new, it can mean a few different things. It can simply be glue between the windings and core coming undone and allowing the coils to vibrate, it can be due to a change in the magnetic core's gap, it can be due to an electric fault within windings such as an internal short between two turns or a number of other things that may affect the operating frequency or load. Most of the faults I can think of should destroy the regulator or severely affect the output so if your 5VSB is working properly, they probably aren't it.

 

[ulysses35]

Is this a high pitched whine ? this is often a sign that a capacitor eiter inside the PSU or worst case on the mobo itself is dying.

You can do a visual check on the mobo caps by checking the tops are not bowed or leaking.. the PSU is a different matter - they are not meant to be opened, but can easily be done so by removing the screws - again check the tops of any caps inside. If any are showing signs of being bowed or leaking then its time to replace the PSU or mobo.

 

[dmfree88]

The whining has changed off and on its not new.. i bought the computer used and it was whining when i first purchased it. the whining seemed to go away over time of me using it i had assumed because of the heavier load i was putting on it then the previous owner. it may have been still going on but it definetly lessened to the point of not being annoying.. i had also done a bios update that seemed to change/fix alot of issues, and about the same time the psu stopped whining so badly. But about a week ago after tinkering off and on with the computers fans i noticed the whine was still there (or was back) and now since then it has gotten worse. I turned it on last night and had horrid whine the entire time i used it while tonight the whine didnt start until about 5 minutes after the computer was on, then increasingly got worse and now is either decreasing or im getting used to it but its still there. Its not a noise i could imagine anything doing right out the box. Id have already replaced it if it wasnt so stupidly shaped/difficult. I should have money for a new one soon i was just hoping for somewhat of an answer to see if rebuild was possible or if the noise was safe/not safe figured the fact that it whines while shut down is strange, i know it got to the point it wasnt doing that at all im guessing it was from cleaning it.. but now its back to crap (still clean i cleaned it once more since). I assume rebuilds probably always possible so long as parts are findable. Maybe I will take it apart and post pictures tomorrow if i dont find an immediate problem. Going to bed for now, check back in the AM.

 

[dmfree88]

couldnt the capacitor be replaced? Its definetly coming from the psu. Obviously id leave it off/unplugged for a few days before attempting any removal/sautering of parts but if its obviously a capacitor isnt it as simple as putting in a new one?

 

[InvalidError]

couldnt the capacitor be replaced? Its definetly coming from the psu.

Before thinking about changing capacitors, you would need to open your PSU and check whether or not there are any signs of probable capacitor failure in there.

Since the 5VSB supply has very low current and low typical load, capacitor failure on it is somewhat unlikely.

 

[dmfree88]

Sorry about the delayed answer i was hoping to have time to look at it before i got back to you. I gave it a minor attempt and stripped a screw that seems to be welded into that S.O.B. LOL. But I am now having issues with the screeching even worse now. Its sometimes very faint but now always there. I noticed when pulling the power plug from the power supply the light on the motherboard doesnt turn off until the screeching stops about 3-5 seconds after plugs removed so im guessing its having some more serious issues.

I have froze in game twice now this evening having to push power button to shutdown and in the past have had issues when shutting down getting stuck on the windows is shutting down screen. sometimes when that happens the graphics card will shutdown and the computer will stay running, during which the hard drive continues to run with the light on (read/write) probably causing problems when i push the button to kill it.

So im guessing its really got problems and im just getting another one... i found a good seasonic 620watt 80+gold that i have to do some rewiring to get to work and some mounting on the outside. But should be much better and not have to worry about another dell crap power supply going out.. the design is really not good its probably just overheated and cooled off too many times with only 2 tiny fans cooling a 650watt psu even at low load is probably not sufficiant.

Once the new one arrives I will get it hooked up and work on finding out the issue with the dell one. I probably wont end up using it but if I find the problem I will try to fix it and maybe sell the dell system when i get a new case/mobo. Anyways thanks for the info, i atleast know what im looking for when i look at it opened up if i can ever get those screws out.

 

[dmfree88]

Best answer selected by dmfree88.

 

[dmfree88]

should mention it popped the #2 and #3 service light when it froze the first time (dell says that means floppy or hard drive fail check power cables) so i checked them and it started after that and worked fine but then froze again.. checked cables again and came back online to here.. havent checked whether it will freeze again.. probably just gonna wait for the new psu before destroying my hard drive due to low power output.. i think this things just old and tired..

 

[InvalidError]

I noticed when pulling the power plug from the power supply the light on the motherboard doesnt turn off until the screeching stops about 3-5 seconds after plugs removed so im guessing its having some more serious issues.

As I said above, the 'screeching' is coming from teh 5VSB circuitry and the LED you are mentioning is most likely the 5VSB-present LED so it would/should naturally stay on until the PSU's primary-side stored energy is spent, which can take in excess of 20 seconds on large high-quality PSUs.

 

[dmfree88]

good to know, and i suppose its not entirely a screeching as much as it almost sounds like an air leak until the powers unplugged then the sound of it stopping is almost a screech. strange noise hard to explain/translate into words. Anyways I will have the new power supply hooked up soon so if its not that easy to replace i wont worry about trying. More wanted to fix it so it will sell with the computer later when i downgrade in size of case/mobo but who knows by then might not be worth it. Thanks for the info