Has your PCG03 always done this?
It's not something I've heard happen before. In Windows 8.1 the time settings are under Settings - Time and Language. The top option is 'Set time automatically'. Whether set to on or off the PCG03 should keep time pretty well, the difference being that when set to on the time will be updated to internet time on each boot.
If you turn this setting off does the PCG03 keep time?