|You must get that idea about System "Idle" Process out of your head so that we can concentrate on what this issue really is. If that rises it means that your computer is then doing very little, so forget about it. Too much background activity will cause your System Idle Process to go "down" not "up". A high figure is a good thing - mine is 98 right now and I am just online. If I closed a few background programs that figure would go even higher.|
Without some other evidence (like another process showing high figures) then there is no reason yet to suspect that your processor is not coping.
The only real fact we have is that your games are not running smoothly so that is what we must tackle - not necessarily CPU overload.
Have your games always been slow? I'm no gamer but I understand that games depend very much on the adequacy of your video, which will be inbuilt unless you have added a card suitable for gaming.
The steps you took in #8 were worth trying.
Reboot simply means powering up - the computer boots into Windows. Reformat might help but it is worth exploring other avenues first because it can introduce other issues.
As per #7 "restarting the computer" (reboot) can sometimes help, especially if you then go straight to your game without running anything else.
Always pop back and let us know the outcome - thanks