x1300 pro in Dell e520?!

I am trying to make this Dell e520 work with my old x1300 pro so it can support shader model 3, so my brother can play at least somewhat modern games, but i cannot make it work for some reason. whenever the card is installed, I just get black screen, no BIOS splash screen or anything. What do I have to do to make this work? thanks.

EDIT: the DVI port is working but not the D-sub (?) so thatll work for now.