Just got my 4225 4 channel yesterday. Installed the software on my home PC to get familiar with navigating the scope. Was able to use the functions on internal generated signals without problems. However, I installed it today on my work laptop, which is also running windows7. After install I used the signals generated by the software once again to test on laptop. Scope module is not connected at this time either. I cannot get trigger to work correctly. If it is set to auto, the screen ill simply slow down and be choppy, as if it is lagging. If I set the trigger to repeat or any other option, the trace will completely disappear. Anyone have any ideas here? I do not want to try using this thing on a car if the signals are going to be incorrect or unusable.