Hi everyone, I’m just wondering but when I install say avast on my PC will the ram that windows defender uses on windows 10 be freed up? I don’t really want two antivirus products using up all the ram if it can be avoided.
Give your PC the Ctrl+Alt+Shift salute and you will see it from the Task Manager indications when you have started up Task Manager,
so you can establish it all by yourself. Summa summarum there should not be any difference in weight on the old cycles. 
polonus
Windows Defender should be disabled by the Windows, when you install Avast (the same for other 3rd party AVs) to prevent conflict.
That said Windows Defender may still have carry out periodic scans still enabled and it would still be updating its virus definitions for these scans. Also some Windows 10 features may still be checking downloads, I read something on that but can’t recall where.
I went into the Windows Defender settings, and disabled these periodic scans and any other thing that could result in a scan/conflict.