I do my best. Also make sure that your computer gets proper ventilation, including your GPU. If your GPU is overheating, then it is due to ventilation. This could be due to its fans not working, and that could be caused by the lack of updates, or a hardware fault. If it's your CPU, then yeah, the thermal paste may need the renewal, and if THAT doesn't work, make sure your computer fans are working.
Keep me posted, but so long as you're in contact with a professional, I'm sure you'll get things figured out soon. Best of luck!