Some things register themselves to run on startup, the idea being that the user doesn't mind waiting another couple of seconds then, but they do mind the same couple of seconds when they click the app icon. So it's *always* running, already loaded in the background, and that might be enough to tie up what it thinks it needs. I seem to remember at least Adobe doing that. Don't know if Chrome does or not; I don't think so.
You can tell Windows to not load those things, with a checkbox for each one. It used to require a third-party app to do that, but I think they've added a tab for it in the Task Manager now. Keep your antivirus on, of course, and any special drivers that you actually use, and disable everything else. Then reboot.