Memory constantly at 90%+ after Windows 10 upgrade

Yesterday I upgraded my PC from Windows 7 to windows 10, and today I started having problems running games where everything was getting very hitchy. I checked my memory and CPU usage and noticed that my memory is now constantly at 90% or greater. The task manager claims that System is using the most memory, but it's only using aroun 250 MB, there is 7.6/7.9 GB of memory being used total. My specs are:

• Intel i5-4670K @3.4 GHz
  
• 8.00 GB RAM @1333 MHz
  
• 64 bit Windows 10
  
• MSI Twin Frozr Nvidia GeForce GTX 770

Is anyone else having this problem, or has fixed it? I looked around on Google and various forums but only found one post that seemed similar, and the person said that the issue involved an Nvidia memory leak and they had fixed it, but didn't explain how they'd fixed it. The post was also about a pre-release version of Windows 10 from May. Here's a link to the post
https://www.tenforums.com/general-dis...ting-open.html
and here is a picture of my problem
https://i.imgur.com/xzzYhXf.jpg?2
https://i.imgur.com/zSp0TWX.jpg?1

Same problem

I lowered ram usage by disabling windows defender, cortana and one cloud. But I dont have such a problem at all. And I have crappy pc but its working excelent. Athlon 5600+ x2, asus m2n-mx se, 2gb ddr2 ram.

I don't know if you have 'Killer Network Manager' installed or not, but if you do, then update it to the latest version here: http://www.killernetworking.com/supp...iver-downloads

It dropped my memory usage in Windows 10 from 90%+ to 30%: https://gyazo.com/2be44ee935bd1fac25aea2743e28784a