There was a lot of excitement in the run-up to AMD's Vega launch, but the cards haven't exactly set the GPU market on fire --- the RX Vega 64 generally offering performance comparable to Nvidia's GTX 1080, which was released last May. So, it comes as a surprise to learn that AMD's flagship outperforms the GTX 1080 Ti by 23 percent when running Forza 7 in DirectX 12.

Our own tests show the RX Vega 64 to be 18 percent slower on average at 1440p when compared to an Aorus GTX 1080 Ti Xtreme 11G, but German site's tests produce a radically different outcome in DX12.

Using a Core i7 6850K overclocked to 4.3GHz and 16GB of DDR4 memory running at 3000MHz in quad-channel mode, the site tested the DirectX 12-ready Forza 7 - released on October 3 ­- using the Crimson ReLive 17.9.3 and GeForce 385.69 drivers, which are optimized for the racing game. Graphical options were maxed out, and 8X multisample anti-aliasing (MSAA) was enabled for the three tests, which each used a different resolution.

In standard HD (1920 x 1080), not only was the RX Vega 64 ahead of Nvidia's 10-series flagship by 23 percent more frames per second, but the RX Vega 56 also had it beat by 18 percent more fps. Things were even more surprising in the smoothness-focused 99th percentile frametime analysis, which showed AMD's RX 580 and R9 Fury X also ahead of the 1080 Ti.

Nvidia's card improved as the resolution increased. At 2560 x 1440, it jumped ahead of the RX Vega 56 (which was still ahead of the GTX 1080) but still lagged behind the RX Vega 64 by 12 percent.

Going up to 4K (3840 x 2160) finally saw the green team's GPU take the top spot, but not by the huge margin one might expect. It leads the RX Vega 64 by just seven fps, and remains behind both Vega cards when it comes to 99th percentile frametime analysis.

Nvidia said the results were unexpected but did confirm the accuracy of the tests. "The ranking in Forza 7 is very unusual. Nvidia has confirmed [to] ComputerBase, however, that the results are so correct, so there is no problem with the system in the editorial regarding GeForce."

It'll be interesting to see if Vega can replicate these results in other upcoming DirectX 12 games, or if Forza 7 will be a one-off. All in all, it looks like good news for AMD.