My trusty and much-loved 8800GT is showing signs of failing, so I'm looking to replace it ASAP. System specs are below, main monitor is a 24" 1920x1200 LCD (with a secondary 19" 1280x1024 LCD as an extended desktop). Games that I dabble with include Borderlands, Fallout 3, Mass Effect 2 and other Bioware RPGs, and a bit of COD2. Budget is £250-300.