That card would probably play any game out today. The newest games, like Crysis, wouldn't play on max settings... but I think Counter Strike would be more than fine.
My only worry with an ATI card is that when I was getting help with Linux on the forums... everyone said nVidia was the way to go because they had much better Linux drivers.
And what if i want to dumb down my graphics card? I doubt i will be doing any hard core gaming, if any gaming at all! Probably just games on websites (flash games ect...).