Why Unreal Engine Default Blank Project Take 15-20% CPU Useage. But Unity3D take only 1-2% CPU Usage?

I have Unreal Engine c++ & Unity3D c# Blank Project.
I deploy both projects. and I test the CPU use of both projects. Unity3D project takes CPU use 1%. but unrealEngine projects take 15-20% CPU use; both projects are blank & both are deployed for PC. Why do unreal engine projects take 20% CPU usage? Can I make any mistakes here?
I try to make simple and small games but CPU usage is very high. I cannot add any C++/BluePrint class. I cannot change any setting. I have a fresh installation of UE Engine.

NOTE: This is Unreal Engine Blank Project of UE5.0, 5.1, 5.2, 4.27. All engines give me the same result. This testing do with deploy game shipping mode & debug mode.

PLEASE GIVE ME A SUGGESTION.
THANK YOU