AMD Radeon RX 6900 XT review: the typical performance upgrade spectrum

We conclude our testing of traditional, rasterised game performance with the Assassin's Creed Unity, released in 2014 and still proving a challenge to this day (and a long-standing Digital Foundry favourite) - plus the more recent releases of Metro Exodus and Dirt Rally 2.0.

In order to deliver precise results, our performance data is more than just a readout of an average frame-rate at the end of a test. Instead, we use the FCAT tool built into Rivatuner Statistics Server (RTSS), which overlays a coloured border to the left side of the screen. Each new frame is represented by another coloured box in the sequence - and its height signifies the time it took to generate. We capture a direct feed of the game footage and border from the graphics card we're testing, analysing the resultant video file with our own tools to essentially write down the frame-time for each frame. This metadata is then uploaded to the Eurogamer website and then rendered by the server into the live performance widgets you see below, allowing us to pick and choose the comparisons you'll find most interesting or helpful - and give you the power to make your own choices too.

Metro Exodus

Metro Exodus reveals another of the challenges in benchmarking graphics cards. While the bar charts look cut and dried in showing us the various frame-rate averages across the spectrum, actual 'in the moment' analysis shows that certain parts of the benchmark see AMD pull ahead, while in others, Nvidia is much faster. We'd hope that 4A Games chose the scenes tested here to cover a cross-section of the game as a whole, but it's not unreasonable to assume that in actual gameplay, AMD may be a lot faster in some areas of any given level, while Nvidia would pull ahead in others.

As it is, the benchmarks paint a vivid picture - 6900XT can't quite match RTX 3080, while the RTX 3090 steams ahead. The actual performance differentials in context though are quite illuminating. What we can say for sure is that - likely owing to the Infinity Cache - AMD gets stronger at lower resolutions.

Dirt Rally 2.0

We'll keep this one short and to the point. The Dirt Rally 2.0 analysis encompasses an entire stage and is one of the longest repeatable stretches of actual gameplay committed to a benchmark. Again, actual differentials between GPU architectures can shift 'in the moment' but the overall trend is clear. At 4K resolution, the 6900 XT moves narrowly ahead of the RTX 3080, but the 3090 is dominant with an 8.3 per cent lead. However, the lead evaporates at 1440p where the top-tier cards are on level pegging. Curiously, at 1080p, Big Navi stretches its legs and delivers a lead against its Nvidia rivals - but the notion of spending this much money on a GPU to run at full HD resolution is almost mind-bending.

Assassin's Creed Unity

After the mighty Crysis 3 was nerfed by a Windows upgrade that limits performance in GPU-bound scenarios, Assassin's Creed Unity is our last legacy game standing - and still a terrific experience, by the way. Back in the day, this benchmark was brilliant for showcasing CPU limitations and for highlighting issues with driver limitations, and so it is today. Performance tops out at 1080p and 1440p resolutions, and it's only at 4K where GPU utilisation comes to the fore - and clearly the Nvidia offerings have the better of Big Navi here.

So that's the standard benchmark suite out of the way, but Smart Access Memory is a fascinating new feature that played out nicely on supported titles in our RX 6800/ RX 6800 XT review - and now its utility has expanded still further.

AMD Radeon RX 6900 XT Analysis

• Introduction, Hardware and Power Analysis
• Doom Eternal, Control, Borderlands 3, Shadow of the Tomb Raider - Game Benchmarks Part 1
• Death Stranding, Far Cry 5, Hitman 2, Assassin's Creed Odyssey - Game Benchmarks Part 2
• Metro Exodus, Dirt Rally 2, Assassin's Creed Unity - Game Benchmarks Part 3 [This Page]
• Smart Access Memory benchmarks and requirements
• Control, Metro Exodus, Battlefield 5 - RT Game Benchmarks
• AMD Radeon RX 6900 XT - the Digital Foundry verdict