I know this may be sound like a noob question but whats the problem with running that hot the card (most cards in general) are designed to either overclock to a certain level or until they hit the 85c limit. So if it hits the limit and tries going higher in temp it will downclock till it stays at 80-85c besides the possible performance degrade what is the problem of running hot. noise is not a factor for me so if i need the fans at 100% i have no problem putting them there?
well put it like this, something gets too hot it stops working basically, or caps explode and effeciency can be ruined, which means a crappy card or in another cases the card stops working period. 85C isn't the limit btw, I've had an amd card reach 102C(never let that happen). When a card reaches its TDP limit a fail safe goes off and you computer hard shutdowns to safe damaging your GPU and other components. However this can still deter the effeciency of the card so I wouldn't even try doing it.
If noise isn't a factor then by my guest get the AMD R9 290, the stock card sounds like a vacuum literally. I can't say much for the non-reference cards.