losing your oc'd performance, when kept stock the cards are getting faster. So.…..
Try the newest driver 19.2.2.
A lot of underlying problems seem to be vanishing like snow with the latest drivers. Lots of patches everywhere , also on windows 10.
You may wanna try to clean your (windows)system because that thing is as vulnerable as soft cheese. Considering this weeks patchnotes alone it speaks volumes about windows state.
Most or all systems are compromised in some way. So start cleaning and updating firmwares aswell. All of it. You may wanna run Privazer next to DDU, just to make sure nothing bad hides on your disks and system.