I built a system a year ago based on a P4C800deluxe-E with an AIW 9600pro in an Antec Sonata case. I like my quiet and early in January I replaced the stock ATI fan with an Arctic Cooler vga silencer rev 3. I did some minor lapping as the heatsink was nowhere near polished, then installed it using the provided thermal paste. I don't OC this computer and things usually run cool; the new vga cooler actually made a difference in the noise level.
I use this machine daily, generally it gets powered up at 0500 and is left on whether or not I am using it till about 2200. Two weeks after the installation I came home one day to find the machine locked up (it had just been sitting there in a blank screen saver); I had to do a hard restart on it but it came back up and ran fine. Same thing happened the next day but this time when I powered back up I had garbage on both screens. Opened up the case and the vid card was HOT. Fired it back up, the fan was spinning, couldn't figure out the problem so I slowed the fan down (by sticking a finger in it) and looked at it in a mirror and the FAN WAS SPINNING BACKWARDS!
Now I have no idea if it had been spinning backwards since the day I installed it because I never in my dreams would have expected that, and I could feel air coming out of the slot at both high and low speeds, and it ran for almost two weeks without a hitch (although this machine rarely if ever gets stressed, no gaming, have not been vid editing lately). My email to Arctic Cooling detailed how the blades of their VGA cooler were in the opposite orientation from the stock hsf but the wires on the plug were in the same polarity, they wrote back saying their fan is designed to run in the opposite direction and suggested I did not have the thing seated properly. I responded that it WAS seated well, when I removed it everything looked correct, it had been firmly screwed together and not overtightened nor was it loose; I have not heard back from them yet (going on a week now).
Most likely I am out the $$$ for that card as I doubt that ATI will honor the warantee with a non-stock hsf and it seems like ArcticCooler, judging by their silence, is not going to do anything either.