High RAM Usage

[Brentar]

So I've got my own little workstation I've built myself, its been running well ever since but there's only one thing that is concerning me. I have 12GB of DDR3 1333mhz RAM.  And at idle it uses anywhere from 2GB to 4GB, with no background tasks running at all. When I'm running my games and whatever else I like open across my three monitors (Secondlife on one screen, chrome with youtube open on the second, and then telegram/discord on the third) it goes up to freaking 8.3GB even 9GB out of the 12GB I have, and I cannot see anything in the task manager that adds up to that much RAM usage. ANd I know for a fact that it shouldn't be that high. I am also aware that I have no viruses because I did several scans with multiple tools (don't even ask what ones).  I've heard that superfetch can cause this problem where it caches a bunch of shit to the RAM or something. What can I do? 

[r4tch3t]

Open up task manager and click on show processes from all users. That amount of ram usage doesn't seem unreasonable.

Just booted my pc and it's sitting at 4.8GB used of 16