Ok the three best are msi twin frozr, asus direct cuii and evga acx
The twin frozr is great, but is the loudest of the bunch, not by much mind you.
The asus direct cuii is not only a great cooler, but is also a completely non reference pcb on the card, and is renowned for it's high quality parts. (also overclocks like a champ). Is also the coolest and quietest of the bunch, but ALSO the most expensive
The evga version also overclocks like a champ, and in fact is probably the best overclocker of the 3 by a very slight margin. It is much better than the msi, but also more expensive in most cases, and is quieter than the msi and cools better, but does not quite cool as well as the asus and is ever so slightly louder than the asus one...