I have the above graphics card and i am having problems with erratic booting.
When starting the pc, it is hit and miss as to weather the GPU starts up.
When this happens, i can hear the cd drives chugging away but the monitor light remains flashing. If i press the reset button, the gpu may start up after a couple of goes. I have monitored the +12v voltage line on startup and it stays at 12v. I have a 650w supply.