I'm moving from an old noisy and power hungry setup to a newer one, faster and more efficient, but I'm considering if is really a good idea to swap the PSU too, a FSP Group Aurum AU-600
(gold rated, 80+) mainly for two reason: 1) it's a bit loud, and 2) may be overpowered.
1) noise: swapping fan?
I did this trick ages a couple of time to fix bad fans or simply noisy PSUs, but I'm concerned is the right thing to do with this one. I have no idea if the actual fan is thermally controlled in the outside or by the fan itself, and if changing the fan with one that has a fixed low RPM would be a good idea.
Apart from voiding the warranty, what's the general opinion here on SPCR about swapping the fan on PSU with quieter models?
Update: there's a Protechnic 2400rpm fan inside, the spec say is PWM (regulated with a bad linear system by the PSU).
I'm considering buying a 1200-1300 max PWM fan. Do you think is a good idea?
2) overpowered but efficient?
I'm planning to build a 65W Haswell with a mid-sized GPU, 1HD, 1SSD, PCI-X audio and not much more. 600W seems a lot for what I'm planning to do (Tt calculator say that I need less than 400W), but if efficency at low wattage is ok with this AU-600 maybe it's ok to keep using it, am i right? Problem is I don't know how good this PSU is with small loads. Any idea where to verify this?
Do I really need to switch to 460-500W to save in efficiency?