More than likely a faulty graphics chip, the mobile Nvidia 8/9 series which you have are notorious for this especially in laptops with less than perfect cooling which allows them to get very hot.
My advice would be firstly to clean the heatsink and fan thoroughly, secondly try a fresh install of Windows with the latest Nvidia drivers. Trying to troubleshoot an installation that has had a lot of random tweaks and settings applied by a dubious program isn't going to go far. If you still have the same problem with a fresh install, it's likely the graphics chip is toast.