Precision 5760 crashes/reboots at 1:08 intervals

Hi all:

I've been pulling what's left of my hair out on this one. Laptop crashes and reboots at exact 1 hour and 8 minute intervals. I've done so many things in an attempt to fix it, I don't even remember what I did. Here's the kicker - this only happens when it is plugged into AC power. When on battery power, it does not crash. BIOS up to date, Windows 11 Pro, all latest updates installed, Dell Command Update, all updates installed. For the life of me, I can't figure it out. Thought it might have been something in Task Scheduler but I've disabled everything except for this one thing that I cannot stop. Hmmm...