We added a few results with Radeon HD 5870 in Crossfire to our VGA database; we stuck to the highest settings (1920x1200 with 4xAA/16xAF) as the system becomes severely CPU bottlenecked at anything lower, the only game not spitting out 100+ FPS at 1280x1024 with this VGA config is Crysis Warhead with maximum details, DX10, 16xAF. There we only get 61.6fps. In all other games tested you need at least a 30" screen to make them suffer a tiny bit.
In short: the Radeon HD 5870 CF setup will only benefit those who have money to burn and monitors to match their gaming rig.
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