When starting, I get no boot screen... it just stays black until the desktop appears, except for a small progress bar in the bottom left corner (see pic). When I try and boot from the Recovery partition or Install USB, I get nothing... the screen stays black. Card is an nVidia GT120 (Mac edition). Now I did try a flashed card in here yesterday, to check 4K support. It gave me the boot screen, but this problem occurred when I replaced it with the GT120. Could this have messed anything up?