Value and Efficiency
Looking over the performance of our test lineup, it's important to keep prices in mind. At a starting price of $300, the Radeon HD 6950 doesn't quite compete directly with the other cards in the group. The Radeon HD 6970 competes directly with the GeForce GTX 570; the two are separated in price by only $20. We included the GeForce GTX 580, priced at around $500, for reference--we thought it would be useful to compare AMD's fastest single GPU against Nvidia's fastest single GPU.
To find out which card offers the best value, we averaged the benchmark results for all our real-world game tests, and then divided by the price to arrive at a metric we call Dollars per Frames per Second. A lower number is better here; it means you have to spend less to get equivalent performance.
The GeForce GTX 570 looks to offer the best performance-to-dollars ratio at 1920 by 1200, but at the higher 2560 by 1600 resolution the Radeon HD 6950 provides value that is hard to beat. The Radeon HD 6970 doesn't offer quite the same ratio as the GTX 570, but it's still a far better deal than the GeForce GTX 580. Those $500 graphics cards are seldom good bargains; they're for price-be-damned enthusiasts who simply need the fastest thing out there.
Here's an impressive chart: total system power consumption. Although Nvidia greatly improved the power utilization of the Fermi architecture with the GTX 570 and 580, those cards still use a lot more power than the Radeon HD 6900 series cards do. In fact, the measured power came in well below the rated maximum power draw for both AMD cards; people who like to tinker with overclocking will probably find lots of headroom before things get too hot. Playing around with clock speeds and the new PowerTune slider in the control panel could yield impressive results, if these power readings are anything to go by.
By dividing the average frames per second of all our game tests by the power use under load from the previous chart, we arrive at a measure of Watts per Frames per Second. Instead of simply looking at how fast the cards are or how much power they use, this chart puts everything together to determine how power efficient they are. Here, again, lower numbers are better. At 1920 by 1200, AMD's new cards are very similar to Nivida's. Crank up the resolution to 2560 by 1600, and they hold a big advantage in performance per watt.
Next: Not a record breaker, but a good deal nonetheless