First I would try to uninstall the current driver then install the newest driver for the card. If that doesn't work the card is possibly damaged. Do you have an old card you can run? if that works, its defiantly the card.
Usually if the game is installed correctly, and the latest drivers have been installed correctly (remove old drivers first) then its likely the GPU is DOA
If the card is new is the PSU powerful enough to quench the 460s thrist? 12v rail output???