Its not pointless getting 2 cards, its just better to get one, it leaves you more room for future, spend your money on one really good card, either the 4870x2 or 295, forget the 280, its upto you whether you prefer Nvidia or ATI, then in a year or twos time, if needed you can then add another card. If you get 2x280 now, you'll have no where to go upgrade wise in future, as adding a 3rd would do very little