Hmmm. Our boxes with the axio systems are similar. The integrator had set them up with 6GB total because they, like most people who ought to be experts, had gotten bad advice. Their thinking was that a processor could reliably address 3 GB and there were two processors, each with its own memory controller...

They were wrong. We had to run 32-bit XP because the Axio drivers were only for 32-bit XP and PPro was only for 32-bit XP.

Your problem is sounding familiar to me but I can't remember what the solution was. The BIOS on our XW9300 systems has a switch to "hoist" the memory above two GB to be remapped at 4GB and above. With the switch on we'd just see two GB, with it off we'd see something like 2.3 GB (lots of hardware in those boxes). One of the settings was unstable and I think it was with the switch off. In your case since you're running XP64, you'd want the switch to be on.

Newer motherboards don't have a switch in BIOS and just automatically remap the memory, but if there's a conflict then I think maybe you don't have a remedy in this case, exept for new BIOS patches or possibly firmware patches for the card. I'm pretty sure this isn't really anything to do with Vegas except maybe the fact that you have to run old BMD drivers to use the card with Vegas.

If you are running /3GB or /PAE switches I'd try turning those off.

Dual Opterons have some other voodoo going on because each CPU has a memory controller, and I think there are a couple of ways to configure them so that they work well together. I don't know if that could be your problem but it's something to look into. My guess is that the advice from BMD was good, but these memory issues are still a black art even for people who ought to be experts.

Good luck with that.

Rob