Fair point for those it works for but it isn't always an option for everyone. I need to keep the sound to a minimum.
Forget the 69xx series then ... loud monsters when the fan gets moving, even at 50%.
Yep, for the 6990s water cooling is the best solution IMHO. Or possibly an after market cooling solution like the one Arctic Cooling built for the 5970 - not sure if they updated it for the 6990. However with such an aftermarket cooling solution you'll be dumping heat inside the case so if you have good case airflow AND you only intend to put one card in the system (like a gaming rig) then it's all good.