Wow...I've never heard anything like this with NetMeeting. However, there is a possibility you have another T.120 app running (there are some nasty issues with running two app-sharing progs at the same time).
You are correct in assuming the PSU *might* play a part, or even be the culprit, especially if it's a low-quality PSU and you're either overloaded with devices and/or you're overclocking.
What would really help narrow this down is knowing your systems specs, OS, video drivers, apps and systray events that load on boot, and any other apps you have installed or running that are capable of app-sharing (such as PCAnywhere or SameTime).
Another thing to consider: have you installed additional fonts (and I mean LOTS of fonts), or have you ever installed fonts from Hewlett Packard?