Yes, that board will accept 2 HD 6850s in Xfire. One on the x16 (PCIe) slot and one on the x4 (PCIe) slot. But I doubt you'll be happy with the results. I had a similar board (Biostar) with x16, x4 and two Sapphire Radeon HD 6850s. The benchmarks I ran with the two cards were only a tiny bit better than the single card. Some were slightly lower. I believe the lesser bandwidth of the x4 slot drags down the performance of the card in the x16 slot. At any rate, it was a fail as far as I was concerned.