Power, Temperature and Noise
Ah, so there's an energy price to be paid for having the highest clocks we've ever seen on a high-end AMD card. Whereas the Asus and Gigabyte cards both run at 1.2V when at maximum speed, Sapphire bumps this up to 1.26V, thus increasing power consumption along the way.
The Tri-X cooler does an admirable job of keeping all that wattage in check. The highest power consumption and lowest temperature is a neat trick if you can pull it off.
Sapphire's balance of temperature vs. power consumption leads to a card that while not loud by any means, isn't as unobtrusive as, say, the reference card or GeForce GTX 7x0. The card can be quietened through the bundled TriXX utility, however.