It's not Nvidia vs AMD screws its Clevo/MSI vs Dell. Clevo and MSI use very narrow specialized screws while Dell uses a slightly larger more standard size that you can often find matches that of other random electronics with narrow looking screws. Clevo moved to the larger size for 10 and 20 series. It sounds like you bought a Dell/Alienware 970m, which needs the slightly larger screws for the x-bracket. You can likely harvest the correct size from newer spare electronics with narrow screws. Ex your laptop's 4 lcd panel screws and 5 keyboard screws match that of the dell x-bracket. For now until you find more screws taking 4 of the keyboard screws should work well. Don't try changing the x-bracket. This is hard on the card and you can easily damage it.