I Have a OCZ 600w PSU with +12V @ 18A. I went from a GTS250 (runs good) to a GTX460 (BSOD on windows logo). So my question is do I need a 500w +12V @ 24A or was the card DOA ?

The Bios boots normal, it's when windows is about to start up when the BSOD appears for one second then computer tries to reboot. When i reinstall my old GTS250 every thing works.

BSOD = Blue Screen Of Death