NVIDIA GeForce GTX 660 Ti at High AA Settings Review

We take the GeForce GTX 660 Ti and compare it clock-for-clock with a GeForce GTX 670 to see what the memory bandwidth difference means at high AA settings. We also take the GALAXY GTX 660 Ti GC video card and compare to a Radeon HD 7950 w/Boost at high AA settings.

Introduction

This will be our fourth article that deals directly with NVIDIA's new GeForce GTX 660 Ti. We've spent a lot of time and resources getting to the bottom of several performance comparisons for gamers, pointing out important information about this new GPU. We started with our original launch evaluation using a GALAXY GeForce GTX 660 Ti GC 3GB retail video card. We made many comparisons and looked at how upgrading from older generation cards will benefit you with this new video card. We then dug into overclocking with the GALAXY GTX 660 Ti GC 3GB video card and found out that it can provide performance over GTX 670 and Radeon HD 7950 when overclocked. Following that, we took this card to the max and showed you how an overclocked GALAXY GTX 660 Ti GC 3GB compares to a highly overclocked GeForce GTX 670 and a highly overclocked Radeon HD 7950 using custom video cards. Now it is time for another performance comparison that many have demanded, and we wanted to show you, super high AA performance.

This article focuses on running the GeForce GTX 660 Ti at super high AA settings at 1080p and 1600p (2560x1600). We are going to figure out how the GTX 660 Ti compares to the GTX 670 since these are the same GPU. We are also going to compare the GALAXY GTX 660 Ti 3GB video card to the Radeon HD 7950 with the new PowerTune with Boost technology at super high AA settings.

Comparing Clock-for-Clock

The first comparison we are going to make is to compare the GeForce GTX 660 Ti clock for clock with a GeForce GTX 670. The reason for this is because both video cards use the same GPU, the only difference is that NVIDIA has scaled down the memory bus width and bandwidth by 33% on the new GTX 660 Ti. The GTX 670 uses a 256-bit memory bus at 192GB/sec of bandwidth, while the GTX 660 Ti uses a 192-bit bus with 144GB/sec of bandwidth. That is "the difference" between the video cards. Therefore, if we can clock the GPU clock speed to the same frequency we can compare only the memory bus differentials and see what that reduction in memory bandwidth actually manifests in gaming performance.

In order to match the GPU frequency we used EVGA Precision software and tuned ever so slightly until we reached the same in-game GPU frequencies with both video cards in every game. That meant we had to look at the frequencies in each game and tune manually until we reached our target. Our target is a 1215MHz GPU clock speed. We selected this frequency because both video cards could easily achieve this, and it's also a decent overclock for both GPUs that almost all [H]er’s should be comfortable with . We were able to attain these clock rates on both GPUs and keep the frequency target during our gameplay scenarios.

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With the GPU clock speed and the memory clock speed being the same between both video cards we can compare and find out what the difference in memory bus means for gaming performance. On pages 2 through 5 this is what we have done. We have taken a 2GB GTX 660 Ti video card, and a 2GB 670 video card and compared these clock-for-clock. We test each game on each page starting with the highest settings and work our way down.

Comparing to the Radeon HD 7950

The second comparison we wanted to make was to look at specific performance differences between the GTX 660 Ti and Radeon HD 7950 with super high AA settings as well. Since it's useless to make each one clock-for-clock because of architecture differences, we simply used a retail GALAXY GeForce GTX 660 Ti GC 3GB video card and a Radeon HD 7950 with the new PowerTune with Boost applied to it.

On August 14th, AMD updated the Radeon HD 7950 with some new technology. AMD introduced PowerTune with Boost on the Radeon HD 7950 to increase its operating core frequency in games. The new frequency the Radeon HD 7950 operates at is 925MHz in games, vs. 800MHz on the launch card. Therefore, we applied this new BIOS provided to us by AMD and compared the GTX 660 Ti to the new Radeon HD 7950.

The most important factor about this comparison to keep in mind is the large memory bandwidth difference between the HD 7950 and the GTX 660 Ti. While both cards have 3GB of RAM, the HD 7950 has a 384-bit memory bus with 240GB/sec of memory bandwidth. The GTX 660 Ti of course has a 192-bit memory bus with 144GB/sec of memory bandwidth. That means the Radeon HD 7950 has a 66% memory bandwidth advantage over the GTX 660 Ti. With a large difference like that we'd expect to see the HD 7950 blow the GTX 660 Ti out of the water when it comes to MSAA performance. That is what pages 6 and 7 will answer for you. The conclusion page will sum it all up.

Test Setup

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The drivers used are the same from the original evaluation and the overclocking evaluation. We used ForceWare 305.37 and AMD Catalyst 12.8 WHQL.