Hi Eldata,

This is fantastic! I must be getting close to the cause of the problem. My scope image is similar to your worst image. Also, when i zoom out on my wave form you can see on every second or third pulse that the baseline continues through without breaking. So this all points to the PC not putting out a decent usable pulse stream. Therefore i make my assumption again that; If my motherboard & CPU combination is capable of passing the "Driver test" with flying colors, then the only other thing this leaves is the parallel port? What do you think....?

Julian.