I need to know if a PCI Express 3.0 x16 graphics card (R9 380 4gb) fit into a motherboard with a PCI Express 2.0 x16 slot? Please answer soon if you know the answer, Thank you very much in advance.
Yes it will work, u are safe to go (u wont notice any difference). Be sure u meet minimum psu reqs for r9 380.
P.S. I am using pci e 3.0 vga on pcie 2.0 slot and it works great.