Back up software, If you Dual boot or use a Linux Portable USB stick, it can cause thr time to be off.
All three of my machines get their clocks screwed up, when I boot up with my USB stick that has Clonezilla on it.
Try this. Configure the system to force-update the time on boot.
To do a force-update you need to run the following as administrator (or system):
SC START w32time task_started
So to force update on boot, you need to run that command as administrator. You can do that using Task Scheduler. To do this run the following as administrator:
schtasks /CREATE /TN "Set Time On Start" /SC ONSTART /RU SYSTEM /TR "SC START w32time task_started"