AS THE LIST of dual Opteron motherboards with AGP grows, a pattern has formed. Where are the motherboards that allow both Opteron memory controllers to be used with AGP? The Tyan K8W, using AMD"s chipset, has appeared in their summer catalog, the first hint of a "good" design, but only as a CAD drawing. So what is the problem?
It seems that when the key elements of two Opteron memory controllers, a NUMA aware OS, such as Suse64, Windows Server 2003 or Windows XP-64 beta, and an AGP slot are combined, the AGP slot is bumped out of it"s normal place as PCI device 0 (zero). This creates a scenario where most video card drivers do not know where the AGP card is, in addition to not knowing which Opteron"s memory controller is closest, and therefore the proper addresses range to use for best AGP performance.
But in some earlier versions of ATI"s fireGL driver set, some extremely optimistic (or forward looking) ATI driver hacker decided to include support for a non-pci-device-0 AGP slot. This particular driver set works just fine with dual Opteron memory controllers and AGP.