I'm using XP, can't see more than 3GB of RAM and thats what I have. The hard drive isn't thrashing when this occurs like you'd think meaning its not a RAM issue (no swapping), it definitely appears to be a video card issue.

I actually have the maxfps 30 and maxfpsbk10 on all of my accounts (only have a GeForce 8600GT 256). All accounts are set to min graphics 800x600 except main is 1024x768 (still minimum graphics) and I have keyclone setting affinity of main + first clone to CPU0, last 3 clones to CPU1.

I can play the game for hours with 5 accounts without any issues, but within a minute or two of using the PiP swap with keyclone my system starts to hang itself.