Unexplained High Memory Usage

I don't think it's my ram because I can use my computer for hours and hours without and sign of problems, but once I leave for about 30 min it slows down. The last thing I downloaded was Windows 10 and I never had this problem back on windows 7. From my own research people have been experiencing my problem on windows 8 and 10, but not on windows 7. So do you think that returning to Windows 7 would fix it?

Incase you cant see it on the picture, I have 8GB or ram and 6.98GB is usable.

Maybe the percent calculation of the task manager has problem. At first, set the memory usages from values to percentage. In my example this is a hungarian Windows, I hope this is at the same place in english version of windows 10:

What shows your task manager if set the memory usage to percentage?

If the percent values seems correct, we need the full list of your running applications.

Yep but we had no idea how much you have installed :)

Looks like from that only 1gb is probably hardware reserved so that is not bad.

You just need to turn some stuff off I would guess = Live titles/ Onedrive/ New updates Botnet /...

http://www.howtogeek.com/224981/how-to-stop-windows-10-from-uploading-updates-to-other-pcs-over-the-internet/

Tried it, and it didn't fix it.

Post what task manager shows on the startup tab.

I ended up re-installing Windows and it fixed the problem.