Hi! For the holidays I'm buying myself a new x1950 Pro AGP, as what I've seen it kicks all other AGP's in the behind. ^^ But I can't decide on two points. Which x1950 Pro (AGP)? 1) What brand to get? 2) Does the 512mb have that much over the 256mb? If so, there's only the Sapphire and Powercolor wha...