I have recently installed 2 identical p3 500 into BrillianX IV, with one CPU it runs fine, with the second cup utilization is at about 30% constantly and it slow and jerky, Fade effect kills the machine. I have tried both MPS 1.1 and 1.4, but I loose the USB support. I have ensured that the correct HAL for MPS Multiprocessor is installed, can anyone help ????