New model Sapphire R9 290 Vapor-X should be quiter and also lower temp in compare with Sapphire Tri-X. I guess Vapor-X will be one of those best in terms of noise and heat. Problem is to find some real comparison because when they test noise they use many different test settings. Different distance from card, level of load on card, open case/closed case/open bench. So you probably wont find direct comparison anywhere.
I personaly plan to go with Vapor-X or maybe with their 290x version.