so i have a gateway Dx4300 and i wanted to upgrade it so i bought a gtx 750 ti and evga 500 watt power supply it took me some time but i got both in there and hooked it up. I hooked up the 20+4 pin to the 24pin the SATA to the hardrive and the 4+4 pin to the 4 pin cpu and it wouldn't turn on. I put the old 300 watt power supply in and it worked fine. IS this psu not able to work with the gateway motherboard? If so that really sucks and i just wasted $50.