VisionTek x1650 Pro power problem ?

I saw it from FRYs for $25 ar and it had HDMI output.. because I really want it to be my HTPC. People complaining about the fan speed, but I don't care, as long as I get one with HDMI and HD support for the future.
But I received it today, and installed it fine. I switch from TV-Out to HDMI output on it, and it recognize my HDTV right away. The problem was it was at 1125 x something, and the video don't play full screen. So I lowered the resolution and the TV went blank. After that I could only hook it up via s-video, and then after that the computer wouldn't turn on at all with this card in. I switch it back to my last card and it went up like normal. I don't know whether I should exchange this or get refund back. Is it the power supply ? I don't have anything to test it, I just have a few 350w and 1x 600w. If it is the power, I was planning on buying a power supply that is quieter anyways.

My motherboard is KN8 Abit
3700+ Athlon 64
2GB g.skills + buffalo
power supply - 600w Echostar
500gb ata hdd

Thanks for your response.

Ooh, so that's what its for.. But my card don't have the power connector on it. I tried hooking a connector to the mb, but that didn't do anything. The TV is Sony Braic 47inch DLP. I also tested it out on a 17inch CRT and both of them didn't work. When I hit the power button it went on for a split second, literally, and turn off.