I'm replacing a EVGA gtx570, 2560mb ram. Love the card, get 24 seconds on Rendertest 2010. I'd like to replace with a used version of the same card. Hard to find the 2560 ram, easy to find 1280 ram, and about 1/2 the price. How important is the video card ram? I'm running an i7, 2.62, 12g ram - editing AVCHD - usually encoding to Main Concept mp4, 720p Internet template. Thanks for your help! Greg