I would use components that Tormach has approved in this document
http://www.cnczone.com/forums/tormac...-software.html
Also when you set up the computer make the software as bare bones as possible. IOW, no internet connection, no other software, nothing. You also have to turn off all sleep modes, screen savers, power savers.
I didn't even load the video card software, just left the generic vid driver that the machine booted up with.
When I go to "add delete programs" in Control Panel there's only one program and that is Mach3.
This machine is flawless and I didn't even exactly follow Tormach's recommendations, I'm using a SSD harddrive. I'm going to build a PathPilot machine also and it will be following the recommended hardware.