Hi, I have a ultra xfinity 500w psu with 2 12v rails. The 1st one has 16A and the 2nd has 18A. I want to get the xfx gf 9800 gt graphics card. I have a amd athlon dual core 4400 with 2 gb of ram, 1 cd drive and a 320 gb hard drive. Will my psu power the card?