HiGame

We covered Ashes of the Singularity and how the game’s DirectX 12 performance has evolved between AMD and Nvidia. This week, Microsoft has launched the PC version of Gears of War Ultimate Edition, but the characteristics of the two titles couldn’t be more different. The new Gears of War is catastrophically broken on Radeon cards.

Jason Evangelho of Forbes has details on the exceedingly strange performance results, of which there are many. The Radeon Fury X is incapable of holding a steady frame rate, with multiple multi-second pauses throughout the benchmark run. The same problem struck the 4GB R9 380 and the 4GB R9 Nano as well. Meanwhile, an R7 370 — that’s a midrange card based on a four-year-old graphics architecture, which also ships with 4GB of RAM — runs just fine.

Here’s the R9 Nano running in 4K at High Quality.

The Forbes tests show two trends. First, GCN 1.0 cards perform smoothly, while GCN 1.1 and 1.2 cards stutter and struggle. Second, AMD GPUs with >4GB of RAM show marked improvement. I spoke to Jason about his results; he indicated this is not the case on Nvidia hardware, where 4GB of RAM gives the GTX 980 all the headroom it needs at settings and resolutions that cripple AMD.* Last year, we surveyed 15 titles to determine whether gamers needed more than 4GB of VRAM to play in 4K and determined they did not. The fact that AMD is hammered at 1440p and High detail suggests that memory management in Gears of War Ultimate Edition is fundamentally broken as far as AMD GPUs are concerned.

One of the historical differences between AMD and Nvidia has been their Day 1 driver support. AMD has put a great deal of work into closing that gap in recent years, but Nvidia is still widely perceived to have an edge when it comes to launch-day optimizations.



The game’s visuals are badly corrupted on AMD cards above 1080p and at higher detail levels.

In this case, however, the problems go far beyond performance profiling. The game isn’t slower on AMD — it’s unplayable on many AMD GPUs. Hawaii / GCN 1.1 is now more than two years old, Tonga is 18 months, and Fiji has been in-market for nine months. None of these are new products.

Developer or driver?

There are several reasons to suspect this is a developer issue rather than a driver problem. First, there’s the fact that DirectX 12 is designed to give developers far more power over how a game is rendered. This can be a double-edged sword. DX12 allows for better resource allocation, multi-threaded command buffers, asynchronous compute, and better performance tuning — but it also makes it harder for the IHV (that’s AMD or Nvidia) to optimize in-driver. There are optimizations that AMD and Nvidia could perform under DX11 that can’t be done in DX12.

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