Im thinking about buying the Coolermaster RP/RS-650-PCAR eXtreme power plus 650w
What do you think?
Oh God no.........
Look, the wattage claims mean nothing. It's all about amps on the +12v rail and efficiency. If the psu doesn't even have a basic 80+ efficiency certification, don't bother.
This is how psu's are classified:
That coolermaster is "crappy 70%".
The psu you have now likely put's out about 300-350w max, not 500w.
Where are you buying from and what is your psu budget?
The power supply is the most important component of the computer, yet I never understand why people trust their new high end parts to some generic piece of crap.