Ok, I just got an Ati 3870 since the fan was going out on my 1900xt. I installed the new drivers, restarted, and then shutdown the computer to make the swap. I'm using 10.5.6 and in WoW, using the *exact* same settings as before, it gets about 5 FPS less than the 1900xt (1900 x 1200, windowed mode, VSync with triple buff, 2xAA, set to Highest Detail) I thought maybe it was something to do with 10.5.6 so I installed the update again via the combo updater. Same results. Any ideas??? Thanks!