You cant go wrong with any cooler by Zalman. Also, the Arctic Cooling Silencer line is a good way to go as well. I would check for compatability with the NV Silencer and your XT. I have owned both companies coolers and they are by far the tops when it comes to VGA cooling.
"It is far better to grasp the universe as it really is than to persist in delusion, however satisfying and reassuring."
- Carl Sagan
Intel i7-5960X | ASUS X99-Deluxe | 16GB Crucial DDR4 | Intel 730 240GB SSD | Crucial M4 256GB SSD
WD 1TB Black x1 | 2 x ASUS Strix GTX 970 SLI | Corsair H110 Water Cooler
Corsair 750D | Windows 8.1 x64 | Dell 2410 x 3 @ 5760x1200
Intel E5-2660v1 x 2 | ASUS Z9PE-D8 WS | 128GB ECC DDR3 | WD 250GB | 24TB iSCSI Shared Storage