My Graphics card isnt detected but powers on but no display.

The integrated graphics are fine and run, but the mobo doesnt detect the gpu.When I plug an hdmi in the gpu it says no signal.If I try to install new drivers off NVIDIA it says cant install because you have no nvidia graphics card installed.Please help.I got this motherboard off Ebay and the seller said everything worked.

Things I’ve tried.

Resetting CMOS

Reaseat Graphics Card

Reset Bios

Try to change setting in bios.

Another graphics card but still no detection.

Updating Bios

Specs:

I5-3470

Asus P8H67-V

Asus RTX 2060 Dual 6G

16gb ddr3 ram

256 gb ssd.