Annoying power supply noise... Only on a cold boot?

[SouthEastBlue]

Been having an annoying problem with my Coolermaster Silent Pro 700W PSU, in that over the last 3 months or so in that whenever I start my computer from cold in the morning it always makes a sort of grinding noise... Not really loud, but louder than all the other fan noise. It never ever does this noise, apart from when it's cold in the morning and hasn't warmed up.

For the noise to go away the computer either needs to be left alone for a few minutes, or alternatively if I 'pat' my computer hard enough it also goes away most of the time. Is this the behaviour of a dodgy fan? If so, it's definitely from my PSU.

It's only roughly 7 months old or so, so I would have hoped it would have lasted a little longer than that. I've also given it a clean when I upgraded my system, and there was hardly any dust inside it anyway. Are Coolermaster returns good? Only problem being, I bought my PSU with a case as a bundle meaning they may want the whole lot back? If it carries on I may just pull the fan out and try to lubricate it, or I guess replace it? Especially as it doesn't seem to happen all the time, and my luck being if I send it off the problem noise won't appear.

 

[Tealc]

Sounds as if the fan is having trouble at cold but once warm it's smooth enough.

When you cleaned your system did you blow some compressed air through the PSU?

Ripping your PSU open will invalidate your warranty of course and a fan swap on a PSU is not a thing you should undertake lightly, it's not that it's not simple enough it's more that it can be quite dangerous.

If you can remove the fan wire cover you may be able to feel the fan turn and check for frictionand possibly be able to remove the blades for inspection of the bearing and motor but I doubt if it will be that easy.

My OCZ fan went (became really noisy) after six months and I did the fan swap because I simply didn't want to be without my PC for 3 months, or however long an RMA takes. It was cheaper to buy a decent fan than it was to buy a new PSU and ship the PSu to the Netherlands so I just did it.

 

[SouthEastBlue]

I didn't blow any compressed air through it, I just removed the fan grill and removed the fan through the open section (warranty sticker wasn't destroyed this way).
I then just blew a very small amount of dust out with my own breath, and wiped over the fan blades to remove the little dust on them. Not really sure how to fully test a fan though other than spotting the noise/grinding/rattle.

I know power supplies are pretty dangerous things to mess with, and I know partially how to drain most of the charge they keep. Been informed before to switch the PSU off, then press the power button on the PC which turns it on for a second or 2, then switches off having removed the power from the PSU. Or leave the PSU for a day or two to decharge itself.

When changing a PSU fan though, it has to be a specific rated fan than matches the original though right? This is where it might be a pain getting one exactly the same, unless it doesn't matter too much? Think I would be more than capable of snipping and joining a couple of cables though.

 

[Tealc]

Well if your confident.

Just don't do as someone suggested on here and lick the capacitors to discharge them, I feel this was rather poor advice.

I replaced my Adda (I think) 2000rpm fan with a 1600rpm Scythe S-flex. I did this based on the fact that this fan is well regarded at spcr for this mod and also because the OCZ unit I modded always blew out cold air due to it's poorly calibrated fan controller. I've no idea about the CM unit you have though. You have to ensure that the fan you use is happy working horizontally, not all fans are and will fail early.