My computer used to become slow after update. I noticed after I occasionally face slowness after window update. CPU workload became extremely high. I don’t know why. Then, I found the following solution to do.
1) Try using the Performance troubleshooter to automatically find and fix problems
- Click on start and in search bar, type Troubleshooting and hit enter.
- Under System and Security, click Check for performance issues.
2) Delete Temp files
- Window + R to call Run box and type as %temp% and hit enter. Delete all files in that folder.
3) Delete Prefetch files
- In run box, type as Prefetch and delete all files in that folder.
Ref : http://answers.microsoft.com/en-us/windows/forum/windows_other-windows_update/windows-7-pro-64bit-is-extremely-slow-after-latest/b3eb9556-2a62-4bf7-be58-4df4f02d339d