Actually ASUS produce AMD based boards too
http://uk.asus.com/Graphics_Cards/AMD_Series/EAH6570DI1GD3LP/
meximexi I think your going to struggle a bit with that graphics card the rest of your system is more than enough but I think you will need to turn of the AA settings even if you game at lower resolutions and likely play at low with some medium settings. Try to upgrade that graphics card when you can its really letting your system down