I got my VIA EPIA's C3 800 CPU working without a fan atm.
The only thing I had to do for it was (horribly) mutilate a heatsink I had still lying around so it would fit the 40x40mm spot. I hacksawed my Volcano7+ (hey, it's pure copper, can't go wrong with that
). I attached it to the CPU with thermal adhesive. Despite its heavy weight it seems to be holding so far. The only real problem I had was removing the stock heatsink!
The motherboard is in a regular Morex Cupid 2677 case. I replaced the stock case fan with a 60mm PAPST fan and removed the metal grill. I also removed some of the fins of those airvents in the case. Namely te ones in the front (there the harddisk is) to increase airflow.
It's been on for 48hrs now without any problems.