Okay, too bad the fix wasn't that easy
Next step is to download MSI Afterburner, go to its settings -> monitoring, select GPU Usage and tick "Show in On-Screen Display". Press OK and without exiting MSI afterburner launch a game in which you have bad performance. Report the average GPU usage - you should see it in top left corner of the game.
P. S. Could you press quick edit on your original post and delete that huge piece of useless info? Would make navigating through the thread much easier.