Looks like your original idea was not the problem Pbolduc... I disconnected all of my loose USB connectors, my printer, keyboard and mouse so that no USB devices were connected to the motherboard in any way and the problem remained. I also found out that my Keyboard does not support PS2 adapters it seems, but no matter. So i did not try to disable USB legacy support in bios as my only Native PS2 keyboard is in storage at the moment but it would seem that is not necessary anyhow.

You mentioned at the end of your first post that "There is also another alternative". Pray tell...