[tempguy9999]

Database doing some housekeeping or backup; virus scan; perhaps automated check for windows updates (patch tuesday is every 2nd tuesday of every month so prob not that); completely separate task fighting the DB or other application layer you sis uses. Something else. Anything else.

It's not something anyone can diagnose from what you say, it could be anything, even weirdness such as a hardware fault kicked off by something else (office cleaner plugging something in?) causing power spike RF interference affecting the network causing mass packet drops and retries (ok, unlikely but it's not impossible, I've heard of such).