I would be all over that Asus TOP for its high factory overclock, cool temps, and really, really quiet fans,heavily modified PCB, with an efficient VRM design to produce low temperatures, improved voltage regulation circuitry, much better Chil controller , specially binned chip and voltage control and monitoring support that you won't find on most other non-reference cards.The thing a straight beast!If you prefer to spend less i would go for AMD's HD 7970 and its more powerful brother HD 7970 GHz Edition have been on the market for a while now. MSI has also launched their HD 7970 Lightning in June. Now ASUS has released the HD 7970 Matrix - a card that will directly compete with MSI's HD 7970 Lightning.ASUS has increased clock speeds to 1100 MHz. That is 50 MHz more than the GHz Edition and higher than any other HD 7970 card, including the MSI Lightning. Memory clock is, with 1650 MHz, also higher than any other AMD card.
The card comes with a powerful triple slot cooling solution and adds many features for hardcore overclockers like support for VGA Hotwire, voltage control, and three buttons for direct GPU voltage control. You will also find voltage measuring points and a Turbo-fan button to set fan speed to 100% on the card.
Price-wise, the HD 7970 Matrix comes at $480, which is quite a price increase given AMD's recent price drops for the HD 7970.The other cards i would recommend are two Sapphire's HD 7950 Vapor-X comes with a large dual-fan cooler that uses the company's famous vapor-chamber technology. On the Vapor-X you will also find a "Lethal Boost" button which switches to a second BIOS with higher clock speeds. With this BIOS, clocks are increased to 950 MHz GPU and 1250 MHz memory.
Pricing of the Sapphire HD 7950 Vapor-X is $330 which is a 10% premium. Also, two MSI's GTX 670 Power Edition uses the famous Twin Frozr IV cooler from the MSI Lightning and comes with a large clock speed boost out of the box, making its default clock speed even higher than GTX 680 stock clocks.That would be a solid choice for the price imo they currently are going for $389.99 a piece that doesn't look unreasonable, given the improved cooling and higher clocks but it's up to you.
P.S. I suggest buying two of any of these cards.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202003#top
http://www.newegg.com/Product/Product.aspx?Item=N82E16814121634
http://www.newegg.com/Product/Product.aspx?Item=N82E16814121671#top
http://www.newegg.com/Product/Product.aspx?Item=N82E16814127685