Hi Guys
Thanks for the response.
Computer is fairly ancient I admit but still operating OK and giving giving good performance for everything I've asked of it running Mach3. It's an AMD Sempron 2200+, 1.51GHz. RAM 704MB.
OS is XP running SP3. Mach 3, Licensed with V3.043.066 installed.
Watchdog timer is turned off. Pulse frequency is 35000..............I created another Mach profile and tried using a lower 25000 pulse frequency, (and re tuned stepper motors), but with same result. It's not a major issue having to click on the reset after each command when using Copy cat, just a bit annoying - everything else seems to be working OK. If I find the cause and a solution I'll let you know.
I've just checked the MB specs and it seems the video is generated on the board itself - don't think it has a separate graphics card installed, although could be wrong - it's 5 years since I looked inside the case as computer just keeps going, so will investigate that area tomorrow.
Thanks for the help.
Cheers
Richard