I have a 8800GT and had some over heating problems with it also. I did some research on it and it turns out this card does run at an average higher temperature compared to other cards.
If its at 72C while under alot of load thats to be expected. My main culprit was the game "STALKER", after having a few crashes I monitored my temperatures which reached 92C!!!!!
If you are reaching 72C running LFS I would suggest upping your Graphics card fan speed and increasing ventilation in your case, my graphics temp only reaches 55C with 19 ai cars on lfs.
While looking on forums to increase my fan speed for the graphics card it turns out the standard speed of the fan is running at around 20%. If you use a program such as Rivatuner you can change it to run at 50% fan speed which drastically decreases the temperature it runs at