Testing For Memory Interface Limitations: All Cards Compared
First, we plotted the frames per second achieved by each card. Then, we used the benchmark results with no anti-aliasing as our 100% reference point and calculated the percentage of this for the other settings. This illustrates how much of their original performance the cards lose when anti-aliasing is applied and no CPU or GPU limitation is in play.
Performance at 1920x1080
Performance at 2560x1440
First things first: these numbers are less sensational than they look. Other benchmarks we've run using different games show that many titles are better able to mask the GeForce GTX 660 Ti's narrower memory bus. Sometimes, a lack of bandwidth is less noticeable, if it is at all. So, it could be a problem or not, depending on the situation.
We did show, however, that the card is very much held back by its 192-bit aggregate interface, even if you're using simple anti-aliasing and normal texture detail. The negative effects of this aren't apparent if you're pushing GPU-intensive settings like tessellation able to shift the burden onto the GPU. Giving the GeForce GTX 660 Ti another gigabyte of memory, totaling 3 GB, is pointless, though. Even games that are modified to support huge textures demonstrate worse performance with 3 GB compared to 2 GB. Higher clock rates help make up for the bandwidth deficiency somewhat, but they don't cure the card's underlying problem. A GeForce GTX 660 Ti with 1.5 GB for a bit less money would probably be a good idea.
So, where does all of this leave Nvidia's GeForce GTX 660 Ti with its 192-bit memory interface? Definitely behind AMD's Radeon HD 7950, which is just a better-balanced offering all around. Depending on how much the game you're running stresses the GPU, and if anti-aliasing is enabled, even the less expensive Radeon HD 7870 could be a better choice. This is mostly the case for poorly-optimized console ports lacking DirectX 11 support.
The biggest problem for the GeForce GTX 660 Ti at this point is its price. If you simply prefer Nvidia's cards and are looking to spend around $300, this card is your only choice (though some partner board are being priced even higher). Should they become more affordable, we'd be more comfortable suggesting the GeForce GTX 660 Ti to anyone looking to game at 1920x1080 with up to 4x MSAA.
Three things surprised us when we started looking at our benchmark numbers. First, AMD's Radeon cards scaled very well with anti-aliasing, especially the Radeon HD 7870. Second, Nvidia’s GeForce cards were able to hold their own well, even at higher resolutions, so long as anti-aliasing was kept under 4x MSAA. Finally, we really didn’t expect to see the GeForce GTX 660 Ti get outperformed by two passively-cooled Radeon HD 7750s.
So what does this tell us?
We aren't saying that anyone else ran their benchmarks on Nvidia's GeForce GTX 660 Ti incorrectly. Really, the card that wins depends on games, settings, and resolutions. This card isn’t a good choice for less demanding titles, but it does make a strong showing when a lot of GPU performance and, relatively speaking, not a lot of memory bandwidth are needed. But this exposes the card's big issue. Nvidia's GeForce GTX 660 Ti isn’t really a premium card. It would need to perform better at higher-end settings to satisfy the folks shopping for a less expensive alternative to the GTX 670. If you're really only looking for a middle-of-the-road card to game at mainstream resolutions and modest settings, the less expensive Radeon HD 7870 is ample.