Its about FSX ,I had about 2 month without flying ,and felt very dissapoint with my PC ,I couln't make a flight ,I felt very bad because something I couln't see ...
Firt of all beware of these ,I read some post about computer crash ,in one of them (here) saids that
I couln't even open IE Its almost impossible to notice that one of the clamps can be out of the base,of all intels 775 ,You have to check very close because it seems normal ,and when is not

I made my first perfect flight from svva-tncc in a long time, without crashes ..

also activate in the bios ,the autofan in high at 50�c ,and Never EVER use the option Overclock cpu(there's no need to) and make a conflict with the frequency of the video card wich could works for example in 133mhz, while you setting the system in 150 ,It can make your system crash too..
depends of where you live ,like a dusty place ,keep a regulary cleaning of the heatsink,and the fan with a brush (I wash my heatsink then dry it) replace the heatsink paste ..
Works for me..