AMD Motherboards: Processor Support

Final Words

The latest AMD Athlon 64 processors bring with them performance improvements, and a new round of potential compatibility issues. Venice, San Diego, and Toledo (x2) all have the 90nm manufacturing advantage and the addition of SSE3 instructions. While they will all potentially work on any Socket 939 board, all three new processors require a BIOS update, which may or may not be available for your favorite board.

In general, motherboards based on the nForce4, VIA K8T890, Uli1689, SiS 756, and ATI Crossfire AMD will likely already have a BIOS released that will work with x2 processors or one will be coming shortly. Those with motherboards based on the earlier nForce3 chipset may not be so lucky - as BIOS' that support x2 on nForce3 are just starting to appear. We are told nF3 support for x2 is coming, but it is definitely coming more slowly. This means most Socket 939 boards with AGP video may not be supported right now with an x2 BIOS upgrade. We say most, because the new ULi 1689 chipset does support both AGP and x2, and some of the older but popular VIA AGP boards have x2 BIOS updates available.

AMD has also added additional "hidden" features in the AMD on-processor memory controller. Additional asynchronous ratios are available at 433, 466, and 500 memory speed on boards that implement the necessary code to access these memory controller features. These options should be available with any Revision E chip if the manufacturer implements the controller option read in BIOS. We saw the additional options "magically" appear on an Abit AN8 Fatality motherboard when a 4200+ x2 processor was used.

Unfortunately the long-rumored 1T Command Rate with Rev. E AMD processors appears to have been just a rumor. We could not run 4 matched dimms at 1T in a motherboard with Rev. E/x2 support. Four dimms still required a 2T Command Rate.

You should consider our list of Official and Unofficial Dual-core support to be a unified Revision E list. AMD tells us that Revision E support is part of the requirement for x2, so you can assume any x2 capable board will also properly support Venice and San Diego.

Fortunately for those shopping for a new Socket 939 motherboard there are many new boards that support Revision E and x2 processors. We hope the information in the article will make your search for a new motherboard for an Athlon 64 an easier process. If we overlooked boards and/or BIOS revisions that belong in our Supported list please let us know.