Drilon_2 :
i can play all games in high fps is 70-80 but it stutters sometimes like 1time in 40-50 secs and my ram is in 100% usage xd
Yes your ram is the reason. Windows has to offload some of it to to virtual ram. This is on your hdd and it's extremelly slow so whenever the game has to acces something thats in the virtuall ram it stutters.
There is a reason those games recommend 8gb of ram 4gb hasn't been enough since 2012.