It sounds like a RAM issue.
I do appreciate your PC ran fine with your old CPU which was also overclocked but these new 3000 series CPU s are effectively using BIOS updates that are in Beta stages as manufacturers roll out updates to solve teething problems.
What speed is your RAM set at?
Usually with a BIOS update or after resetting it the RAM will default to the 2133 speed.
There should be an option to enable DOCP profile for the RAM which alters the timings to run the RAM at the targeted 3200 MHZ.
You can enable the DOCP profile to get it to 3200 MHZ then try manually downclocking it in the BIOS to 3000 MHZ to see if it will run stable.
Also try your PC with just 1 stick of RAM at a time to see if 1 of the sticks is the issue.
You will obviously need to place the single RAM stick in the appropriate slot as it differs for single/double sticks.
In Windows search bar type 'memory' and run the Windows Memory Diagnostic tool to test your RAM.
No need to do the intensive test as that takes hours.
Usually takes around 15 minutes to run the moderate one.
Andy