I dual boot into Linux and everytime I do so, so it seems, my Win10 time is reset to +5 hours. e.g. instead of 8PM, it is showing 1AM.
I am not sure if Linux is just a correlation, not a causation.
Could it be my battery went bad? However, if so, why does it roll the clock forward precisely 5 hours.
5 hours is the typical time difference between the US and European countries. What do you have the location and language set for your system?
You need to set BOTH windows and Linux to use LOCAL TIME or they will continue to reset the system clock incorrectly.
I had the same problem with a Windows/Ubuntu dual boot system. The issue was the same as mentioned in the previous posts. Linux and Windows use different techniques (local or UTC) to set the system time. You need to set them to be the same. Here is a link on how to fix for Ubuntu:
http://ubuntuhandbook.org/index.php/2016/05/time-differences-ubuntu-1604-windows-10/
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