This question is about AMPs , not watts
im trying to upgrade video cards to a gtx 750ti which requires 20A on the +12v rail.
Currently i have a no-name psu with Output +3.3V@28A, +5V@30A, +12V@15A, -12V@0.8A, +5VSB@2.0A
so im thinking of upgrading to a corsair with Output +3.3V@25A, +5V@20A, +12V@38A, -12V@0.8A, +5VSB@3.0A
(motherboard Asus m4a785t-m)
my question is this , what runs on the low voltage rails, because thats where i will have access to less power(or amperage). I really have no idea what draws from them, or if the lower amperage is still enough.