Some times the attributes can be misleading. I have seen a spec ask for (just of the top of my head for an example) 256mb video card that is shader 2.0 compliant. Now that covers an awful lot of cards but dosent mean to say every card that can meet that spec can actually run the game.
Usually you will get a card listed as well so it would then be say 512mb video card DX9.0c and shader 2.0 capable Radeon X1950 pro or above.
Anyway as said if you give us more info then we can help more.