I finally acquired a 9800GX2 video card very inexpensively. Plugged it in, spooled it up, and... it is folding, but one of its two cores is only folding at about 2/3 speed, and two of the three remaining 9600GSO cards are only folding at 2/3 speed as well, resulting in hardly any total folding improvement. Initial theories are that either I don't have enough system memory to match the video card onboard RAM (2GB system, and 384x3 + 1GB = slightly over 2GB for the video cards), or it's a squirrelly issue with mixing video cards running different numbers of shaders on the same motherboard.
So... Anyone want to buy four identical 9600GSO or perhaps a 9800GX2 video card cheap?
I'm not looking to create a second caseless dedicated folding machine, and if I can't mix the cards either one flavor or the other will have to go.