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Architectural efficiency
Now that we have some performance and power results, we can illustrate the efficiency of these GPU architectures by generating some of our beloved scatter plots.

In each of the plots below, the most efficient solutions will gravitate toward the top left corner of the plot, while the least efficient ones will tend toward the lower right corner.

We're using measured performance and power from Crysis 3 here, since we have both sets of results. This is system-level power use, as shown on the previous page. Our key comparison from an architectural standpoint is the R7 260X, based on Bonaire and the very latest GCN technology, versus the GTX 750 Ti and GM107. As you've no doubt gathered by now, Maxwell appears to be much more power-efficient than the latest iteration of GCN, and not by a little bit.

Although area concerns have taken a back seat to power efficiency in Nvidia's last couple of GPU architectures, the GTX 750 Ti wrings measurably higher performance across our suite of games out of a slightly smaller die area than the R7 260X.

Want to know the impact of Maxwell's larger L2 cache? Compare the GTX 750 Ti to the GTX 650 Ti. They both have a 128-bit, 5.4Gbps memory interface, with 86GB/s of bandwidth on tap, yet the 750 Ti performs much better. Of course, things other than the cache size have changed, but memory bandwidth generally remains a major constraint. Also compare the 750 Ti to the R7 260X, which has 10GB/s higher memory bandwidth yet is slower overall.

As one might expect, the GTX 750 Ti is among the most efficient GPUs in each of these categories, which means it makes very effective use of its on-chip graphics resources. The most striking contrast here is in shader flops; in theory, the R7 260X nearly doubles the peak rate of the GTX 750, yet the two cards perform about the same in our suite of current games.