The Coolermaster 690 case you linked to has two 120mm fan mounting locations on the side panel. Install a 120mm intake fan in the lower location. It will blow fresh cool air toward the video card.
I've had good luck with Scythe S-Flex 120mm, 1600 rpm, 28.0 dBA, fans.http://www.newegg.com/Product/Product.aspx?Item=N82E16835185006
Lmeow - I took a look at newegg.com. They only list the Scythe Ultra Kaze, 120mm, 3,000 rpm fan. Noise level is rated at 45.9 dBA. That's right up there with the old Panaflo and Delta fans.