I wanted to upgrade my desktop that I got from Newegg with a graphics card, so I checked the detail page and saw that it had a PCI-E x16 slot. I googled it and saw that PCI Express 3.0 x16 graphics cards work with PCI-E 2.0 slots but I couldn't find anything that confirmed that 3.0 works with a normal PCI-E x16 slot (Non-2.0). Forgive me if someone already asked this I couldn't find it.