Recommended power supply

[slippyjim]

Hi,

My friend has an i5 system and is upgrading the graphics card to a GTX770 so Im looking for a new power supply for him.
The 770 needs 42A @ 12V

Ive found 2 coolermaster PSU in his budget
B700 55A on 12V & 20A on 5V & 3.3V
GX-650W 52A on 12V & 25A on 5V & 3.3V

Firstly will they be good enough?
Secondly which one is best?
Is the extra 5A on the 5 and 3.3V rail worth sacrificing 3A on the 12V rail?

Thanks

 

[Someone Somewhere]

I'd tend to avoid CoolerMaster; their PSUs aren't that good, excluding a couple of models.

Look for something 550W+ from the second link in my sig.