Palit gtx 460 recognises monitor but wont display

[richjohnes]

I have recently installed a new palit gtx 460 card. The primary display in the first slot works fine no matter which monitor is plugged. Add the second screen via the 2nd dvi slot and the nvidia control panel and windows recognises the screen is plugged in but i get no picture. If i boot off the 2nd slot only then i get nothing at all, throughout the boot. switch to the first port and I can see the screen. Any suggestions before i send it back?

 

[richjohnes]

Incidentally, the control panel claims that my primary display is connected via vga, which it isn't. No on board graphics, 500w psu with both 6 pin connectors plugged in. Thanks for reading.