i reckon it be the exhaust fan or the cpu fan as they are the ones that spins at higher rpm ish

take off the cpu fan and see if it still makes the noise...but u would neeed the head sink glue thingy if u take it off

or just do my "ghetto mod"

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Chinese Mexican
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My gaming pc is quite loud due to the 2 x 7800gtx's in SLI and the power supply mostly, really annoying when trying to sleep :P

Recently upgraded my noisy home theatre pc to a silent one using a 9600GT silent video card (big fuckoff heatsink), corsair hx-520 power supply, Zalman 9600LED CPU cooler and a Noctua 80mm ball bearing case fan and the system is so damn quiet.. generally the larger the fan the less noisy it is as it can push more air at a slower rpm..

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MY02 WRX STi - sold :(
'12 Golf GTI

Goto DSE, by some compressed air in a can.

Open case, spray air on dusty fans, get rid of all the dust and you should be alright.

It's important to do this every 6 months or so as there is some serious build up of crap in there over the many hours of operation.

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Should have bought an STI

cpu fan will alter its rpm to the temp. very rarely would you psu fan be noisy as it doesnt spin that fast as most psu fans these days are 120mm fans.

most of the time its a case fan or a gpu fan.

Do this and your cpu will fry in seconds!!

Best to remove case side cover with power off and de-dust all the internal fans with a toothbrush and vacuum....Should take no more than 5 minutes. You can also oil the bearings on the fans if you have more time up your sleeve: remove the sticker off the back of the fan motor and apply 1 drop of sewing machine oil to the now exposed hub/shaft.

Or run water cooling like me!

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[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]

Usually this problem is caused by either a fan/multiple fans that spins too fast, or more likely a sleeve bearing fan that has a collapsed bearing. If it is caused by fans spinning too quick, it would have been like that since the start, but if it has just started making the noise recently it will be a collapsed bearing. These are quite common, I have had one on my CPU and one on my GPU. It should be fairly easy to tell which fan is the problem, you can open the case and see where the noise is coming from, try wobbling the fans while they are off (the one with the collapsed bearing will wobble a fair bit more than the others. The easiest way I have found though is to have it running and tough each of the fans with your finger. If the noise changes, it is the fan that you have just touched that is the problem. Simply replace the fan and its all good.

Usually you can replace the fan without removing the heatsink, just unscrew it from the heatsink, but it probably depends on the type of fans/heatsinks your computer has.

psu is often one of the noiser fans - you can get silent ones or quieter ones with large slower spinning fans

same goes for cpu fans.

however video card fans are trickier.