The Guru of 3D tested the performance of Radeon HD 4850 and 4870 CrossfireX
"Guru3D posted a Radeon 4850 and 4870 Crossfire review. Since Radeon series 4800 cards offer so much value, it might even ne interesting to pair them in CrossfireX mode.
Much like NVIDIA's SLI offerings, AMD's ATI solution can be paired and matched as well. So pretty much today we'll place several cards together in CrossfireX mode, first the cards paired (two) and then we'll for the sake of it see if we can pair three cards CrossfireX mixed, meaning 2x 4870 and one 4850. When you compare the results to NVIDIA's latest high-end single card offerings, the results are a little shocking."
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Radeon HD 4850 and 4870 CrossfireX test
