Originally Posted by trog100
treat the 3870 x 2 the same as the old 2900xt.. 15 or 16 amps per card or per rail.. 19 amp rails would be best..
two 3870 cards would run off one 19 amps rail with some to spare..
do your maths is easy to work out..
ps.. think three 19 amp rails or a 750 watt psu for a pair of x2 cards.. the cpu rail dont need 19 amps but they tend to come that way..
so you guys are talkin amps an rails an all that other crap. what is the wattage rating on a psu used for? an what am i lookin at here under the output specs for a psu with 2 rails? - "+3.3V@28A,+5V@34A,+12V1@20A,+12V2@17A,-12V@0.8A,+5VSB@2.5A" thanks!