I guess it has 3V, 5V, and 12V 24-pin ATX power connector (normal connector) & 12V 8-pin connector (the one you're not sure about). Means you need a EPS12V type power supply. I recommend Antec type power supplies as they haven't failed me at all. But they have a big 550W PS in that form. Look around on your online shops to see if they have a different brand with EPS12V