New Mobo

[cropwell]

Don't be so sure.? . . It could easily be a lose or bad connection causing intermitant problems or wire thats breaking but not yet broke fully.? Double and triple check the wires/connections before doing anything else.! . . Esp the PP cable.

If the PC has quick time on then take it off.
Disable any screen savers or energy saving features. If any of the electrics, like BOB etc use USB then it needs setting so windows doesn't automaticly turn it off after a period of inactivity. This is often a cause of USB crashing machine but Mach3 getting the blame.!!
Disable any programs that automaticly check for updates IE: Windows update. Adobe products are a pain for this and I wont have any on my computer that runs machine.

Done all that, completely reinstalled Mach3, used Driver Test.exe, got Goldilocks results, too slow, too fast, and just right. Smooths out as the motor velocity setting is lowered, but too slow to use, and still sounds poorly.

[JAZZCNC]

Done all that, completely reinstalled Mach3, used Driver Test.exe, got Goldilocks results, too slow, too fast, and just right. Smooths out as the motor velocity setting is lowered, but too slow to use, and still sounds poorly.

When you re-installed Mach did you use your existing XML or make a complete new setup.?

Clusting straws a little but if you used existing XML it could be corrupted so for sake of 10mins it may be worth re-entering the settings into a new profile just for elimination purposes.?