Might be your cooling, I had a same problem where it got up to 105, which sometimes even turned my PC off.
I would check my cooling if it's ok or what so ever, my problem was with thermal paste, it wasn't aligned right with my cooler and processor so it got really high temp but now it's all good it around 50.
Might as well be the problem with the air, maybe your something is blocking air to get into the PC or you haven't cleaned your coolers (/PC)