A quick Google, b/c I wasn't sure myself, showed that 2 x 4870X2s will run on an X48, but looks like some folks have issues with FPSs , scaling, and some games not taking advantage of the 4 GPUs.
But then again, one 4870X2 should be ample power for a 24" monitor. So the benches show, again, depending on the game.
Penewah!
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