I'm having this issue now as well. Out of nowhere I go from running smooth as silk to doing like 5 fps. It has killed me a couple times even. I never had anything like this happen before. Is it just me or is it happening during battle mostly?
Doesn't happen all the time and it's not about how many people in PT. I pt'd with 8 and it was fine and then pt'd with 2 and it happened.
win 7 x64 6gb ram.
core i 7
ati 5850 updated drivers.
1tb HD just reformatted for the last patch so it's not some fragmentation issue.