Graphics card compatibility

Looking for some assistance on this one, if possible. 

I have a friend with a Dell XPS 8300 desktop who recently bought a new power supply and robust graphics card (Powercolor PCS 380) to run more graphics-intensive games. Upon installing the drivers and swapping out the included graphics card for the one he bought, the system refuses to display anything on the monitor (connected via HDMI). After troubleshooting for about an hour I did some research and discovered Dell decided not to release a BIOS update to support UEFI devices. With that being said, is there any way that he would be able to run this card on his desktop, or would he be better off returning it and purchasing one that is compatible with this motherboard?

Any advice is greatly appreciated!