After windows 7 updated and restarted it shows 98-100% CPU usage in task manager. But, it doesn't show any heavy process or thread using it. Are they hidden processes that the task manager doesn't display.
even when I clicked a button
display processes from all users it doesn't show any like this. And I am pretty sure that there are no viruses as Antivirus updates daily. But, can it be a Virus processes that usually task manager can't display? this can be another question inspite.