I have a gtx 280 and i was trying to do two power supplies then a i bought a evga 500watt power supply when the dual power supplies one for the pc one for the gpu (but they were grounded together) was not working i put in the 500 watt psu and it is still not working i have a dvi to hdmi the dvi is on my gtx 280 ive tryed it on multiple tvs and none work and i know the drivers are installed correctly because i installed and when i put a vga into my integrated graficts it says it has been disabled is their a problem with the compatibility???