GTX 960 not working

[Robbie_12]

I recently bought a GIGABYTE GeForce GTX 960 4GB WINDFORCE 2X OC EDITION to replace my gtx 650. and when i install the 960 and boot up the computer it gives me a blank screen with a white flashing underscore on the top left after the lenovo start screen. do i have a bad card or do i need to update something, can my computer even handle it?

 

[popatim]

Sounds like uefi security is detecting the hardware change and blocking the boot process. In the bios; Try enabling csm mode and if that doesn't work change uefi mode to legacy