I tested my new memory with memtest86. No errors found. After doing some further troubleshooting, what I narrowed down my issue is a little strange but I have fixed it. I have Plex running under docker. On one of its setting where you define the Transcoder folder location, I have misspelled the transcode folder entry. It was supposed to be "Transcode" instead of "transcode". As soon as the media content is played which require transcoding, it will run for a minute or two then reboot the server. After correcting the spelling, system is running stable again. I thought my finding can help someone if they run into the same siltation.
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