400 Watts psu with a MINIMUM of 26 amps on the +12 volt rail
I have not seen a psu that delivers 26 amps per +12 volt rail, so get a good power supply.
I recommend an Enermax Liberty that is a 620 watt.
Perhaps a cooler master that is a 850 Watt.
Get a ROHS compliant power supply, it help the enviroment and it helps witth the monthly power bills :wink: