Stop linking this NV-biased source. We are talking about a guy who crapped all over one of the most legendary GPUs of all time - the HD 7970. He called it short-lived videocard and over time removed his entire article. This is pure gold:
"The most interesting thing about this launch is that it appears that Tahiti’s HD 7970 may be short-lived. AMD’s 28nm yields are known to not be great and the specifications of the new GPU indicate that something strange is going on. The chip itself is quite complex with 4.3 billion transistors but its core only runs at a very conservative 925MHz. Most telling is that its performance is not that great except in DX11 games and especially in heavily tessellated scenarios – only about 25% faster than a GTX 580 overall." ~ Reviewer credibility drops to 0.
On launch date, with "crappy" AMD drivers, 7970 OC ended up 48-80% faster than GTX580 OC.
And now this has been revealed:
"I run my benches a bit differently than other sites which use completely default settings for their HW. I have consistently benchmarked my games with the Power Draw/Limit and Temperature targets of all hardware (both AMD and Nvidia) set to their maximum which means my results tend to be a little higher for the high TDP cards." ~ More here
Translation - since Kepler era, he has run NV OC GPUs against AMD GPUs operating at stock because of how NV vs. AMD GPU boost works.
There is only 1 consistency about BTR or ABT GPU reviews after BFG left -- they are consistently biased, with settings manipulated to make sure NV cards win.