on some newer mobos (i think the new soyo kt3 ultras) have an option where if the cpu fan drops below a certain rpm the computer will shut down. I think it would be pretty easy to use a visible flow meter with an impeller inside and sorta hook it up like they did in that overclockers.com link above. you could place a tiny magnet on one of the impeller blades and use the hall effect sensor the same way its used inside fans. you could probably find a way to mount the sensor on the outside of the flowmeter. that way the hall effect sensor would report the rpm of the impeller the same way it reports the rpm of the armatures inside fans. then just hook up the modified flow meter to the cpu fan power socket and the mobo would moniter the impeller rpm thinking it is a fan cooling the cpu, and when ever the impeller rpm drops below a predetermined rpm the computer will shut itself down
|