Why didn't they use it on the R9 290 series came out would have solved the heating issue probably. it has three freaking fans on it.sorry if this was mentioned before but I just wanted to hear other peoples opinions on it.
It's cheaper to slap on a vapour chamber with some fins than it is to add on heatpipes.
Nvidia's reference cooler is pretty much the same.
It also is nice for them to have a cooler design that will work in any case as long as the card fits. Open air coolers don't have a place in every case but blower coolers can work literally in any case with a little air flow and enough room for the card.
Reference prefers blower styles to keep the hot air from building up in a tight case. It's supposed to work in every scenario. The 7990 is 2 chips. It's so hot that a blower wouldn't work, they deemed a blower would barely work for the 290x so they preferred to use it. Just happens its still pretty hot.
Because AMD wants to have a card that can work in all occasions. Thats where the blower style fan is required, cases that have very poor airflow, a Blower-Style cooler can do just fine. a massive case, a blower-style will do good.
In theory, AMD could of just made a Re-Vamped 7990 Style Cooler on the R9-290/R9-290x but it would of probably overheated in small cases. Now you can argue, that some non-blower style coolers won't overheat in insanely small cases, for example i have R9-290 Tri-X from Sapphire, I have it in a Silverstone FT03. I only have two 80mm fan intakes pushing air towards the card, and one exhaust fan. my card has never over-heated. but for someone who would, lets say have an MSI Twin-Frozr card in a Silverstone FT03 Mini case [Which is an ITX version of the Silverstone FT03 (which is mATX) case] it would probably over-heat but you'll never know unless you try it.
Overall AMD did it, to remove all these scenarios of issues that may occur. Some can argue the non-blower-style fan would overheat in a tiny space, and some could argue it wont. it depends on where you have the GPU and how much airflow you have in the case.
May not be official but the Sapphire Tri-X is basically this and it works great.
For reason why not see above.