Early DirectX 12 games show a distinct split between AMD, Nvidia performance

Joel Hruska 

One of the major questions readers have raised over the past year is which company’s graphics cards would perform better in DirectX 12. It always takes a certain amount of time to answer questions like this, and DX12 is still in the early stages of deployment, with only a handful of titles currently available: Hitman, Rise of the Tomb Raider, Ashes of the Singularity, and Gears of War. Of these four, one of them (Gears of War) is DX12-only and available solely through the Windows Store; the other titles can run in DX11 or DX12 and support multiple operating systems.

Tweaktown recently put Hitman through its paces in both APIs. In 1080p DirectX 11, Nvidia wins top overall honors with the Titan X squeezing out the Fury X. Switch to DirectX 12, however, and AMD’s Fury X pulls ahead. The gap between the AMD and Nvidia cards continues to widen as the resolution rises; AMD wins 4K in both DX11 and DX12 and the gap in 4K DX12 is large enough that the R9 390X is able to surpass the GTX Titan X, as shown below:

Hitman’s 4K DX12 performance. Image by Tweaktown

These results are broadly similar to the benchmark results we saw in Ashes of the Singularity a few weeks before that game shipped. As in that title, Nvidia gains nothing in DirectX 12 and suffers some small performance regressions.

DirectX 12: A bifurcated story

Of the four DirectX 12 games currently in-market, Ashes and Hitman are wins for AMD and show a marked advantage in that API. Rise of the Tomb Raider, on the other hand, is a major Nvidia win. Benchmarks performed in that title show that AMD still lags Nvidia, even when testing in DX12 and even at 4K.

Rise of the Tomb Raider. Data by Overclock3D.net

We can’t really draw many conclusions from Gears of War; the game appears to have been a terrible port with unplayable performance on AMD hardware, and is less than stellar even on Nvidia. The developer has released several patches, but it’s not clear if the game’s been truly fixed yet. With Fable Legends now cancelled, our early performance tests in that title don’t tell us much, either. Still, three games is enough to point to at least the beginnings of a trend.

First, we see AMD picking up performance relative to Nvidia in two of the three titles here. Both Hitman and Ashes use asynchronous compute, but Hitman’s lead render programmer, Jonas Meyer, noted at GDC 2016 that doing so only improved AMD’s performance by 5-10%, while Nvidia gained nothing from the feature.

One reason AMD GPUs do better in DX12 than their Nvidia counterparts is because the new API eliminates a great deal of driver overhead, and AMD’s drivers were never as adroit as Nvidia’s at handling these workloads in the first place. AMD’s 4K performance in DX12 is roughly 10% faster than in DX11, which jives with Jonas Meyer’s comments at GDC 2016.

What’s less clear is why Nvidia consistently loses performance in every DirectX 12 game published to-date. The GTX 980 Ti is faster than the Fury X in Rise of the Tomb Raider when using DirectX 11 or DirectX 12, but it leads AMD by roughly 9% in DX11 and by just 2.4% in DX12. These performance drops aren’t large in and of themselves, but if moving to DirectX 12 makes AMD 8% faster and Nvidia 6% slower, you’ve got a net performance shift of 14% in favor of Team Red.

DirectX 12 appears to help AMD by both reducing driver overhead and allowing developers to leverage GCN’s formidable asynchronous compute capabilities. It’s less clear why Nvidia continues to struggle with delivering absolute performance improvements in DirectX 12, even in titles that otherwise favor the company’s products.
It’s still too early in the DirectX 12 / Windows 10 product cycle to draw absolute conclusions about which architecture will prove definitively better and the imminent arrival of new GPUs from both companies will render the question at least somewhat moot. So far, it looks as though AMD gamers are generally better off using DirectX 12 when it’s available, while Nvidia owners may want to stick with DX11, even when gaming in Windows 10.

We’ll continue monitoring the situation as new titles arrive and will update you accordingly.