Originally Posted by
Xuvial
Assuming you've connected and powered your GTX560 appropriately, I'm immediately thinking that the mobo is still displaying the signal out the integrated chip.
Hook up your monitor to the integrated video on your mobo. I don't know the exact process, but you need to go into BIOS and find a way to disable the Integrated card - could be somewhere in "onboard devices" menu or similar. That should automatically make your GTX560 as the primary display.
Then connect the monitor to the GTX560, it should work.