I have had problems with the pulse engine and onboard graphics, I have also had no problems whatsoever with onboard graphics.
I could almost say for sure the Smoothstepper would solve your problems but as you know nothing is a certainty especially when we are talking computers. As an example however, I have a pico mobo, it has onboard graphics, embedded CPU, onboard LAN, Serial, PS2 for mouse and keyboard and 4 USB ports and all together its smaller than two credit cards sitting side by side
As an experiment I installed Mach on it and ran the drivetest, it crashed about 2 seconds in, then hooked up the SmoothStepper (Beta one) and it ran my mill every bit as good as the full size computer did, in fact it was actually better.
There are still a few things to do to the PlugIn for the SmoothStepper, sync for lathe threading being one of them but I have no doubt that this will be completed soon.
Hood