I think exactly the opposite thing. Good 790FX boards are much better than good 790GX boards. I think M3A32-MVP, DQ6, M2R, K9A2 Platinum should overclock PhII higher than the newer 790GX boards. The "old" boards have been designed for extreme OC of the older Phenoms, but their OC potential was poor(of the cpu's and of the boards because of SB600) and 790GX came as a solution with SB750 lowering the production costs of the boards. M3A79-T Deluxe and the DFI SB750 solutions should perform similar to the old boards.
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