Tim, yes, I tested the RAM last week as well. I have two 1 gig sticks, so I tried one, then the other alone. No difference. I then used MEMCheck on the full 2 gigs and they came up clean. I also used HotCPU (I think that was it) and the CPU also passed.
Again, this isn't an incompatibility that existed out of the box. This is something that has progressed over time and has simply gotten worse and worse. Again, this is what leads me back to the motherboard itself, and we all know how complicated they really are down at system level.
At this point, all I'm waiting for is definitive word from Sony that it is the motherboard before I go out and spend a bunch of money I can't spare. (Let's face it. I've got nothing but Socket 478 P4s and there's only one motherboard available for them and even at that, I'll still need to buy a new video card because it doesn't have an AGP slot, only PCI express 16).
At least the wife's computer is running Vegas fine for me, when I can use it.