Date: Monday , November 28, 2011
On Friday, November 25th, 2011 AMD released a driver that provides CrossFireX support to Radeon HD 6000 series owners in Skyrim. This comes two weeks after the game was launched on November 11th, 2011. Now that this driver is out, we can evaluate Radeon HD 6970 CrossFireX performance in Skyrim which we did not get to do in our Skyrim Performance and IQ Review. In that evaluation, we were able to look at GeForce GTX 580 SLI, and the gameplay experience it delivered, but we were not able to make comparisons to Radeon HD 6970 CFX at the time.
This evaluation today will look at Radeon HD 6970 CrossFireX performance in Skyrim and compare it to GeForce GTX 580 SLI. We will also look at GPU scaling, and see at what efficiencies SLI and CrossFireX are working with a fast CPU in this game. We are also going to find out what the highest playable settings are with Radeon HD 6970 CrossFireX. We will also look at some image quality comparisons to hone in some debate about FXAA and Transparency AA image quality in Skyrim.
AMD Drivers - AMD just released Catalyst 11.11b Performance Driver on November 25th, 2011. This driver specifically brings CrossFireX support to Skyrim, but only on the Radeon HD 6000 series of video cards. The previous generation, Radeon HD 5000 series still does not have CrossFireX support, and that will come later in a future driver. This is very important to note, only users with Radeon HD 6000 series GPUs, will get this CrossFireX support at this time with this driver.
Also note, that with this driver you do not need Catalyst Application Profile (CAP 11.11 CAP2) installed to get CrossFireX support in Skyrim. The CrossFireX support is built into the driver itself for Skyrim, and is not associated with a CAP file. However, for all other CrossFireX support in games, you will want the latest CAP installed so you get CrossFireX support in your other games. It won't matter if you have CAP installed for Skyrim specifically though.
NVIDIA Drivers - The latest drivers possible right now are still ForceWare 285.79 and these provided SLI support in Skyrim the day before the game launched.
Our test system consists of an ASUS P8P67 WS Revolution motherboard, Intel Core i7 2600K at 4.8GHz.
To start off our testing, we first needed to see how the single GeForce GTX 580 and Radeon HD 6970 compare to each other. The settings we used for all these comparisons are at 2560x1600 with 8X MSAA and FXAA turned on at Ultra game settings. The reason why we enabled 8X MSAA and FXAA at 2560x1600 is to stress the video cards, especially in multi-GPU. This game tends to be CPU lenient, and we have to artificially stress the GPUs by using very high AA settings, putting the burden back on the GPUs.
Our run-through starts at the top of Dragonsreach and continues through much of Skyrim through forests and heavy snow conditions.
On a base level, GeForce GTX 580 is faster than Radeon HD 6970 in Skyrim, even with the new Catalyst 11.11b Performance Driver. The GTX 580 holds a 27% performance lead over Radeon HD 6970 at these GPU intensive settings.
Now we can compare GTX 580 SLI to HD 6970 CFX. In the test below, the settings are the same, 2560x1600 8X MAAA and FXAA at Ultra game settings.
With Catalyst 11.11b Performance Driver installed there is a definite performance improvement with Radeon HD 6970 CrossFireX now. Performance is now over 60 FPS most of the game with Radeon HD 6970 CFX. However, GTX 580 SLI holds a noticeable performance lead over HD 6970 CFX. The performance difference is 26%, in favor of GTX 580 SLI. This level of performance difference was noticeable in this game, even over 60 FPS.
Now that we have seen how GeForce GTX SLI and Radeon HD 6970 CrossFireX compare, we can see how each one individually improves upon the single-GPU video card.
The tests below, are once again performed at 2560x1600 with 8X MSAA and FXAA enabled with Ultra game settings.
Up first, Radeon HD 6970 CrossFireX Scaling.
Radeon HD 6970 CrossFireX
This graph shows that CrossFireX is most definitely working with Catalyst 11.11b Performance Driver in Skyrim. It is great to finally see this support come to Radeon HD 6000 series owners. The percentage improvement with CrossFireX is 82% faster performance with two Radeon HD 6970 video cards, versus one. This is a positive and acceptable percentage increase with CrossFireX. It is true that Battlefield 3 scales even better, but this is pretty much higher than average for most other games we have seen. Considering this is a DX9 game, and can be CPU limited, this amount of scaling is impressive.
GeForce GTX 580 SLI
Now we can do the same with GeForce GTX 580 SLI, and see how it scales as well. With GTX 580 SLI we are seeing an 80% GPU scaling performance advantage with two GeForce GTX 580 video cards, versus one. Therefore, HD 6970 CFX has a 2% scaling advantage. Honestly though, 2% is very small, and will vary quite a bit in-game depending on the area you are in. With a difference this small, we can conclude that SLI and CrossFireX scaling is the same in Skyrim.