We came across a few curious benchmark results, posted by Chiphell, and they appear to show AMD's upcoming R9 300 series GPU in action.

Codenamed or nicknamed 'Captain Jack', the grog loving GPU delivers an average 20-25% performance uplift compared to last year's R9 290X. It also ends up 15-20% faster than Nvidia's GTX 980. Needless to say, these figures should be taken with a grain of salt.

The card is not out yet and we have no clue how (or even if) it was actually benchmarked, not to mention the lack of drivers that would offer proper support for a new GPU. Chiphell has a chequered track record, the site leaks a lot of stuff, sometimes it is spot on and sometimes it just isn't. In any case you can check out the original thread here.

In terms of power efficiency, Cap'n Jack ends up at 197W (average load consumption). This compares favourably to the 290, which sucked up 242W in the same test, not to mention the 290X in Uber mode, which clocked in at 279W. 

While it is vastly more efficient than previous AMD cards, the upcoming GPU still needs a bit more power than Nvidia's Maxwell 2.0 cards, as the GTX 980 ran on 191W and the GTX 970 needed 167W. However, depending on the actual performance levels, it is possible that matey Jack will end up with superior performance-per-watt.