Question 16.1 GB of hardware reserved RAM, and stuck at 1067Mhz ? (RAM is not new)

[silver12345]

Title explains it, one day I turned on my computer and noticed my games were running slower, bios is up to date and no windows updates happened around the time of the problem.

https://imgur.com/a/CJ4MNiP

View: https://imgur.com/a/CJ4MNiP
(what my task manager looks like)

 

[rgd1101]

full system spec?