The motherboard in my original garage PC decided to throw in the towel and I bought a cheap AMD-based replacement which did not have integral PP. I bought with it a cheap PP PCI card which worked fine for a year or so with my BOB, so no electrical compatibility issues. Although I ran LinuxCNC on that hardware, I did try a demo copy of Mach3 which seemed to be happy with the PP card as well. Motherboard and PP card both came from Novatech. I have to admit that I am in the middle of moving to a Mach3/Ethernet/CSMIO. but only because of the CSMIO and nothing to do with hardware problems or reliability. Seem to be some good reports about the UC100/300 motion controllers, which might be another way around the PP problem but not sure about them with a lathe (I'm running a router with my system).