Heres the problem, 512mb's is great, unless your card cant really take advantage of it. The pro is a great card for the price, but is outdone even by a 256mb xt . At smaller resolutions, 10x7 or 12x10 the xt dominates. But as you go up in res, you just wont get the ability from the pro to outdo the xt even with 512 mb's. Go for the xt, youll have no regrets