Memory usage 6gb after windows reinstall

Solution
Make sure windows is up to date. There is an issue with windows update taking a lot and that looks to be the issue with svchost and trustedinstaller taking that much. There's also some other updates you have to download manually to fix the issue if it continues.
Have you checked your system out using SysInternals tools? They are an excellent toolset offered for free by Microsoft.
https://technet.microsoft.com/en-us/sysinternals/bb842062.aspx

6-7gb of ram use is "not right". My first two guesses would be corrupt user profile or virus. I've seen equal amounts of both.
The first is simplest. Create a new profile. reboot. login on the new profile and observe how the PC behaves.
The 2nd and you'll have to do some scanning with tools like Malware Bytes anti-malware (free version)
 
I`m not sure what you are asking.

If you have a total of 8Gb of ram fitted to your system.
Windows once loaded into system memory will take about 2Gb of the main system memory.

Leaving you with, or it should quote 6Gb of memory space free for other programs.

What you also forget is that overtime with windows applications you install sometimes auto start after windows has loaded, each one takes a chunk of memory space.

Where as when you do a fresh clean install of windows, it is windows that is using a part of the 8Gb of system memory as the OS is memory resident all of the time. As it stands that should be the case.

The more programs you install that want to auto run after windows has loaded will eat into what it currently quotes as free memory for other programs.


Use system information of windows to verify how much ram is physically installed.

Bellow will be what is in use by windows being loaded into system memory.

And it will state how many Gb of memory is free for other programs to use.

1.5Gb of memory used is about right as windows os resides in system memory.

At 83% of free system memory I see nothing wrong at all.

1.5gb used by windows OS with 6.53 Gb free memory. Add 1.5gb to 6.53 showing and you get 8gb of initial system memory.

Wheres the problem apart from reading things wrong ?
 


I did scan no viruses found but after restart i see now it only uses 35%
 


but when it was using that amount of 7gb i couldn't open browser or any other programs
 


Well if a re-start fixed it, then just write it off as a 'hiccup'. If it continues to happen, try to trouble shoot it. If the virus scan came up empty, testing with a different user profile is also a pretty simple test. (if it happens again and you need to test)
 
Make sure windows is up to date. There is an issue with windows update taking a lot and that looks to be the issue with svchost and trustedinstaller taking that much. There's also some other updates you have to download manually to fix the issue if it continues.
 
Solution
Anyway i done clean install and went to windows 10 and it works perfectly the memory just stays at 23% but i really appreciate your help

i couldint do nothing at all on windows 7 i couldint open programs no resources my ram was full at 7gb