Bryce wrote:

If the CPU misses servicing the clock interrupt or other bad
stuff, the operating system's idea of time will suffer, but
the hardware clock keeps right on ticking.

So, if you're losing time without a reboot, the CMOS is
innocent and the O/S and CPU aren't doing the right dance.
If the time is wrong from the gitgo, then the HW clock is
the culprit.

Bryce

Good points. The computer loses time when it is running.
It is the way the time is updated by the cpu/kernel.
I am running linux.