Going back to the 2nd link of 3, maybe it holds true? Perhaps you have some sloppily written 3rd party code somewhere?
Check your start up items (Start, Run, MSConfig, StartUp tab)
Also check running processes in task manager, and see what they're for (somewhere like Viper's page is a good start, his site is still down, so
here is a back up of it), and any non standard non-microsoft would be the first to disable/eliminate from your lines of enquiry.