Hi there and welcome
Which version of windows is running on the DC that keeps getting slow?
On both of them click on the time and go to Date and Time settings and its there you set it to get it automatically.
Let me know the results please
I cant get the screenshots at the moment, but its Click Time, Click Date and Settings, Click on Set Time Automatically
How far do you get?
yes, that's the next step, can you do that please if you do not have the Tab
Let me know the results.