Frame Rating: GeForce GTX 660 Ti and Radeon HD 7950
Battlefield 3 (DirectX 11)
Battlefield 3™ leaps ahead of its time with the power of Frostbite 2, DICE's new cutting-edge game engine. This state-of-the-art technology is the foundation on which Battlefield 3 is built, delivering enhanced visual quality, a grand sense of scale, massive destruction, dynamic audio and character animation utilizing ANT technology as seen in the latest EA SPORTS™ games.
Frostbite 2 now enables deferred shading, dynamic global illumination and new streaming architecture. Sounds like tech talk? Play the game and experience the difference!
Our Settings for Battlefield 3
Here is our testing run through the game, for your reference.
Under our FRAPS data you see that the HD 7950s in CrossFire appear to be faster than the GTX 660 Tis in SLI, but after taking out runts our observed average frame rates are much lower, more in line with the single Radeon HD 7950.
Our now familiar frame time plot data demonstrates the problem with AMD's CrossFire technology and runt frames - frames taking up such a small area of the screen that they adversely affecting animation performance. While both single GPU results look pretty good the HD 7950s running in parallel produce the mass of orange alternating long/short frames. NVIDIA's GTX 660 Tis in SLI are definitely slightly more variant than the single GPU options but appear to be within reason.
The minimum FPS data shows the GTX 660 Tis in SLI running well ahead of any other option with average frame rate of about 122 FPS while the rest hoever in the 70 FPS range.
The GTX 660 Ti cards in SLI definitely exhibit some more frame time variance than the single GPUs but the Radeon HD 7950s in CrossFire definitely skew things dramatically. While this doesn't definitely detect stutter it is a good indication that you will see some with results like this.
Again the Radeon HD 7950s look great in CrossFire on the outset, ahead of the GTX 660 Ti cards in SLI. But after removing those dreaded runt frames the "real world" performance of the GTX 660 Ti cards is much better.
The Radeon HD 7950 combo actually looks worse at 2560x1440 with more variance on a frame to frame comparison where as the NVIDIA GTX 660 Ti cards appear to be tighter, resulting in a better multi-GPU environment.
Our minimum FPS percentile data shows great results from both the single GeForce GTX 660 Ti and the Radeon HD 7950 but adding a second HD 7950 doesn't change much for AMD. Only the GTX 660 Ti is scaling.
Again at 2560x1440 we see the frame variance ratings are much higher with the HD 7950s in CrossFire.
Eyefinity with CrossFire continues to be an even worse problem for AMD as we can see here there are tons of not only runts, but flat out dropped (never shown at all) frames that bring the observed frame rate down considerably.
Ech, a mess of color here. The blue lines are telling us that the 2GB version of the GTX 660 Ti are struggling with 5760x1080 in SLI mode though they are reliably showing frames to the gamer. Single GPU results (though kind of cut off at the top, sorry!) are much smoother but are definitely faster on the single HD 7950 than the single GTX 660 Ti.
The minimum FPS chart shows the single HD 7950 ahead of the GTX 660 Ti, as we expected based on the plot of frame times above (22 FPS average against 27 FPS average). But while CrossFire sees basically no observed frame rate increases the SLI result jumps up to 38 FPS or so at the 50th percentile. Note though that SLI in this case does follow a curve that brings the frame rates back down in line with a single HD 7950 at the tail end.
Our frame time variance chart has really interesthing things to tell us, starting with the expected "AMD CrossFire isn't working that well" kind of thing. AMD's CrossFire clearly sees the most frame rate differences though NVIDIA's SLI isn't immune here with frame variances crossing the 15 ms in some fringe cases. To put that in perspective though, CrossFire HD 7950s see variances larger than that for more than 20% of all frames rendered!