I'm really considering the 256mb x1800xt for my new rig, especially since it's $205 shipped for the oem version. Before I buy it however, I know that 512mb of vram makes a difference at higher resolutions. I'm getting a viewsonic vx2025. Would I need/benefit from 512mb of vram? Where can I find benches that include both the 256 and 512 mb versions of this card? Thanks in advance.