Conclusion: RD580 Performs, But It Does Not Win
ATI's new Crossfire Xpress 3200 is a newcomer that does not fail to impress from a technical point of view, but is somewhat ambiguous. On the one hand, the RD580 is a great core logic product that manages to outperform its Nvidia arch rival in many disciplines, simply due to being the more advanced and more sophisticated Northbridge product. 16 PCIe lanes per port are great, and having these inside one piece of silicon is the best possible solution. (Nvidia would seem to agree, since its C51 will not be very different.) Performance is not an issue anyway, since all Athlon 64 core logic products perform more or less alike. Given that multi-lane PCI Express logic is power hungry, the power consumption numbers of the RD580-equipped Asus A8R32-MVP look pretty good, and the overclocking margins that are possible move the new building block into enthusiast heaven.
Is it all good for ATI, then? Not quite, because the Radeon Xpress 3200 suffers from ATI's chipset shortcoming: the Southbridge. Currently there is only the SB450 Southbridge, and the combination of RD580 and SB450 simply cannot compete with state-of-the-art products such as the nForce4 family or Intel's current top core logic offering, as well as others. (Please check out our articles in the Mobos&RAM section for more details.) There is ULi's M1575 Southbridge, providing better Serial ATA and RAID options, but it still cannot make up for the full care package that Nvidia managed to put together over time.
That said, the Crossfire Xpress 3200 with SB450 is probably the most affordable dual x16 solution on the market, since Nvidia positions its nForce4 SLI X16 only for the high end. As our benchmarks prove, dual x16 PCI Express is what you want if upgrading a second graphics card is an option for you, because of its nice scaling.
In terms of a 3D solution, the Crossfire Xpress 3200 and a pair of Radeon X1900XTX graphics cards is the best performing team money can buy today. But ATI needs to upgrade the Crossfire Xpress 3200 from being just an excellent Northbridge to offering a complete solution for customers who want it all. The SB600 could be this step, but the firm needs to hurry, since Nvidia's C51 and MCP55 are not far off.