Loud motor sound, PSU, Boot up.

Sadamto

Distinguished
Jan 15, 2010
16
0
18,510
Over the past few months every time I start my start my PC up after being completely switched off the PSU will start making a loud motor sound which doesn't go away unless I nudge or hit the PC. However this sound doesn't appear when the computer starts up after being in sleep mode or when restarting.

I'm not entirely sure if it is even the PSU, I've checked all the fans on my PC and there are no wires interfering or any visible culprits. The PSU is an OCZ 700 SXS.

If I wanted to would I be able to replace the PSU's fan easily without having to buy a specially made fan?
 
First you can try and see if tightening the screws that hold the PSU in place will solve the problem. Could be vibration.
If not, could be the PSU's fan. I don't know how accessible the fan is inside the PSU, but you could try to replace it if that's what you want. I would just return it (if it is still in warranty) and get another one.
 
I think you need to pinpoint where the noise is coming from.

Start the pc up with the side off and see if you can locate the area of the noise.

+1^Check all screws etc.

If you thnk its the fan you can carefully remove from the psu and plug in independantly to see if it makes the same noise, it may just need a bit of lubricating or you may find something in the psu casing.
 

kaosnkorruption

Distinguished
Nov 13, 2009
62
0
18,640
My CPU fan does that occasionally when I start my PC from an off state (which is rarely). I have to stick my finger in there just enough to rub along the fins, slowing it down some. It eventually stabilizes and the noise goes away. Sometimes tapping the side of my case will cause enough vibration to jostle it into stabilizing itself.
 

Sadamto

Distinguished
Jan 15, 2010
16
0
18,510
I'm not able to locate visually what is making the sound but nudging the computer stops it or dissipates it shortly until it builds back up (noise). I know it's a fan due to this. It seems the computer has to have been off for an hour or so before this noise appears but I can have the computer asleep for hours and there's no sound on awaking, really strange.

I have filters on the intake fans which were very dusty recently and even when clean still cause significant air flow loss. I cleaned the two on the side panel and had 2 successfully quite, fresh power ups. Could it be something complicated like air pressure being too low in the case due to the filters and the fans working to extract air are being forced to work too hard on start up?

I'm positive it's not my hard drives.
 

Psychoteddy

Distinguished
Dec 7, 2010
605
0
19,010


Ignition timing is off. Should be 3 degrees before top dead center. You may want to consider a cam adjustment too.

OH YOU WERE TALKING ABOUT YOUR COMPUTER!!! :ouch:

Probably just a fan or a rattle somewhere. ;)