AsRock Extreme 4 won't detect GPU - 7870

[Kasraa]

Hi
I just bought a new build but the motherboard cannot detect the vga which is
Sapphire 7870 2GB
i5-3570K if that matters
2x4GB Corsair XMS3 2000
750w

I've read almost all of the topics discussing the same case but even solved ones couldn't help.
I've already:
-Upgraded the BIOS.
-Tried different PCIe slot.
-Tried latest AMD drivers.

The vga looks fine the fans are spinning.
And the power cables to the card are both connected.
Please help I badly need to figure out what's wrong ASAP it's driving me crazy.

Thank you in advance.

 

[Kasraa]

It was the driver problem:|
I've been reinstalling drivers since I bought this guy and it suddenly started to work.