AMD Dual Graphics: Not Ready For Benchmark Results
AMD’s Dual Graphics technology, once referred to as Hybrid CrossFire, allows the APU to work cooperatively with a discrete graphics card to deliver higher game frame rates than either component flying solo. At first glance, this seems like a great way to extract value, offering an upgrade path not available on any competing platform.
Unfortunately, there are limitations. First, this is a software-based capability that only works with DirectX 10 and 11 game engines. Second, the APU is quickly outclassed by most discrete cards. So it really only works with Radeon HD 6450, 6570, and 6670 boards, maintaining balance between the two parts.
We've long since wanted to dig deeper into Dual Graphics; after all, as you can see in the screen capture above, AMD claims it serves up a serious performance increase. But in our subjective experience, this feature does not necessarily appear to yield smoother game play. For the company's Richland introduction, we were excited to finally test Dual Graphics using our FCAT tools, capturing the raw display output and analyzing the stream to determine if frames were being dropped entirely or rendered in a series of full and tiny (runt) frames.
Unfortunately, our video-based analysis turned up an unexpected issue that prevents us from reporting the performance of Dual Graphics. Intermittently, we'd see a frame rendered, followed by a piece of the following frame, a piece of the original frame, and the rest of the following frame. This artifact is accompanied by a tear across the screen as Dual Graphics puts the two frames together.
It's consequently impossible to run our FCAT analysis on the output, since the frame sequence can't be measured. Fraps-based testing in this case would clearly be inaccurate. So, it's better to hold off on trying to quantify the performance of Dual Graphics until AMD can provide a solution that composites the frames free from artifacts or tears. The company is aware of our findings and is working to address them. As of yet, though, we don't have an explanation of why this is happening.
