The straight-line performance of the Nvidia GeForce GTX 680, with its ever-so-slightly pared-back GK104 GPU, is impressive.
Up against the GTX 680 it's only just off the pace, but put it up against either of AMD's top Southern Island cards and it's a winner. It's around the same price as the Radeon HD 7950 and performs as well, on average, as the AMD Radeon HD 7970.
Win and win.
In SLI configuration too the second tier Kepler card is a beauty. It's significantly cheaper than the crazy-expensive GTX 690 and gets incredibly close in performance terms.
The GTX 680 pairing is still the performance choice, but needs a hefty PSU and some neat air-flow configurations to keep them working happily in the confines of a PC chassis.
All the benchmarks were run on the highest comparable settings at the eye-popping 2560x1600 resolution, apart from the Shogun 2 test which was run at 1920x1080.