Mac Pro 4.1 gigabyte gtx 980 ti problem

Hi guys,
I bought a video card gigabit nvidia gtx 980 ti.
I installed the web driver WebDriver-346.03.15f05 because El Capitan wasn't compatible with the previous
WebDriver-346.03.15f04.
I put the new graphic card but it doesn't work.
In the Nvidia driver panel it appear
"pci10de,fb0"
what can I do?
thanks