This is compatible with many many gpus.
REVIEW
INSTALLATION GUIDE
I am also including the R9 290X KIT
NEW Revision 2 supports more cards:
rx480
ATI R9 270X, R9 290X, R9 290 and R9 390/X, HD4850, HD4870, HD4890, HD5830, HD5850, HD5870, HD6850, HD6870, HD6950*, HD6970*, HD7850, 7870...