The GTX should have a built in App called EVGA Precision. In this app you can up the speed of the internal fan that is in the GFX card.
I run the GTX 470 and with the fan set to run at auto it only kicks the speed in higher than default after 55C. You can manually raise the speed on the fan and get your temps lower.
It will be a bit loader, but regardless of water cooled, the GTX is encased, so it has tendencies to build up more heat than an exposed GFX card that has the heat sink and fan visible and is not shrouded.
It is a reference card, the 590s will over heat. There are no dual fan setups released yet, but that may change as I heard EVGA, MSI and ASUS will be releasing dual fans soon. The card has stupid power, why no one has released a dual fan setup is beyond me.