Interference with parallel port step signal timing due to motherboard
video access is usually less for modern motherboards, and does not
matter at all unless you are running the legacy Darwin parallel port
driver. For any system running an Ethernet or USB connected
motion controller, video interference is not an issue.
Video performance can still matter. Mach4 uses Open GL video
drivers and needs reasonably good hardware. If you are running
G code files with megabytes of short segment movements such as
photo carving, you will need to have a couple of Gigabytes of
memory available for video, either motherboard or dedicated card.
Steve Stallings
www.PMDX.com