I'm running Ubuntu 9.04 using P5. The 3D graphic performance is great but I notice a hitch in the flow every 7 or 8 seconds. Looking at screen savers that use OpenGL I get 8 secs of smooth and then a stall and then it runs again and then stalls for a brief moment, over and over again. The stalls are millisecond not half second but it is there. Is there anything I can do to optimize my performance? -thanks iMac i7, 10.6.2, Parallels 5