New Quiet Power Supply

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1

Hi There,
I have upgraded my pc case from a NZXT Tempest to a Fractal Design R4 in the hope of reducing some of the sound coming from my system, tonight was the night I moved all the components from my old case into my new case. However, all was not quiet as expected because the fan on my psu is now really rather loud under load, as loud as the stock cooler I used to have on my GTX 480 when running furmark. This can not do!!! I'm not sure whether the fact the new case requires the power supply to be fitted upside down compared with the old case has anything to do with it or not, or perhaps the power supply is on it's way out?
Any recommendations on a new psu that's very quiet or perhaps some ideas on how to resolve the problem?


My System:


Case: Fractal Design R4


Motherboard: Gigabyte GA-EX58-UD5


CPU + Cooler:  Core i7 920 + Thermaltake Frio

GPU: Asus GTX 480 1.5GB with Gelid Icy Vision Cooler 

PSU: Coolmaster iGreen Power 600W (Product No. RS-600-ASAA)
 

2

get a higher wattage psu, and it will generate less heat....

3

The thought had crossed my mind but for a decent psu, say xfx 750w then we're talking at least £80. Anyhow, I bit the bullet last night and opened up my power supply and I am pretty sure that the bearing(s) are what is causing the noise so I am just going to look into getting a new fan for my psu.
Any recommendations on a fan good enough to cool my 600w that is as quiet as possible. The stock fan is 120mm and is rated at 470mA at 12V. I was thinking something along the lines of putting a Noctua NF-P12 fan in there but wasn't sure whether such a fan would provide sufficient airflow and cooling so I need a second opinion. Thanks