PCI Express not detecting graphic card

Solution 1:

Your motherboard has two PCIe x16 slots. One is wired for PCIe 3.0 x16 and the other one is PCIe 2.0 x4 (but in x16 form factor). The former one is preferred for graphics cards, but you can use the other one to test if the graphics card works.

If it does, then the main slot is broken, but the other one will work fine (although the card may perform slightly worse).

If it doesn't work in either slot, but the same card works in a different PC, then it could be a software problem. I'd start with a clean install of Windows (make sure your backups are up to date first).

Your motherboard also has 2 DisplayPort outputs that you can use with active adapters to drive VGA displays. Or even better, if your monitors support digital connections (DVI-D, HDMI or DisplayPort), use these.