RAM not clearing?

[Flames99Fuse]

This has been a very inconsistent thing, but occasionally I'll boot up my pc just to see that none of the programs I was using the night before closed, and all of my RAM was intact despite having powered down the PC and having it disconnected from power for 8 or more hours. I've tested it every possible way I could think of to see whats causing the issue. I shut down my PC and do nothing else, still happens. I shut down and turn off the surge protector, still happens. I shut down and unplug the surge protector, still happens. I shut down and unplug the PC from the surge protector, still happens. I use my PC every day for gaming and occasional paperwork for work (and school in the near future) and always shut it off around 11:00 PM, then I boot it up again around 7:30 AM, 4:00 PM if I have work (or school).

So basically I'm just wondering if it's my OS (Win 10) or my PC. Or does RAM not clear on shutdown, but rather when the current is grounded?
I don't remember my build, but if it may affect the results, I'll figure out what it is.

[stealth80]

Are you sure you are shutting down and don't have hibernation enabled?