All video cards are backwards compatible with DX versions. A video card that is DX11 will support and work with all games, and previous versions of Direct X. The issue is that the first Operating System to support DX10 options and above was Windows Vista. So if you are running XP, yes the card will work perfectly fine for you, you just will not have any of the DX10 or DX11 options available to you to be turned on inside of games, they will simply be greyed out, or not there at all.