Well you should lower the graphics settings, disable advanced rendering, disable smoothing animation, play in windowed mode (not full screen)---all this helps, but won't fix the problem. Also play short game sessions, spend minimal time in CAS, and the less CC, store items, EPs and SPs you have, the better/longer you'll be able to play for. Even if you do all this, the game will still crash and the overheating will wear down the system eventually, just an fyi, but it will help the situation. The best thing would be to play it on a Windows system.