Power Supply Question

[AnarchyInTheUS]

A question that I have long been wondering but never asked:
How do you determine the right amount of wattage for your rig. I built my own rig, and I think the power supply might be kicking the bucket, but I wanted to know how you determine what power supply watts you need.

Aside from that, I wanted to know if these number look alright:
Vcore: 1.52 Volts (OC so don't really worry about it)
+3.3: 3.06
+5: 4.89
+2.5: 2.67
+12: 11.78
-12: -12.94

My fans are starting to make weird noises, and I wanan know if my generic POS power supply is the problem...

 

[PCHPlayer]

The +3.3 looks a tad low. The others look OK.
Fan noises are generally caused by dust build up. Blast it with canned air or open it up and clean if you feel adventurous.
[Don't try this at home]Just be sure the capacitors are discharged before you open any power supply. [/Don't try this at home]

 

[2336]

Another tip for noisy fans. If you look on the back of the hub generally there is some type of manufacturer's label. Peel that back and you'll see a small rubber/plastic plug. Pop that off and using a toothpick place one or two drops of clean 30W motor oil in there. For sleeve bearing fans it will quiet them and give you a couple of months more life before they finally bit the dust. For ball bearing fans you can get an extra 50% or more run time on them before they croak. Just don't go overboard it'll make a mess. Hope that helps.

 

[AnarchyInTheUS]

Ah, I thought that might be the cause too. I haven't cleaned out my case in a while and i noticed that when I blew off one of them the fan seemed to operate better. Thank you for the input.