Introduction
When AMD unveiled the Radeon RX 6000 series, the company’s emphasis was on delivering better performance across all three of its newest GPUs for gamers – the RX 6800, RX 6800 XT and the RX 6900 XT. Powered by the RDNA 2 architecture (which also powers a custom AMD-made GPU for the PlayStation 5 and Xbox Series X and S consoles), these GPUs are also behind AMD’s line of high-end cards made to compete head-to-head with NVIDIA’s top-tier models from their RTX 30 series.
We have already checked out the RX 6800 XT, and I found it a worthy competitor to NVIDIA’s GeForce RTX 3080 despite its lacklustre ray tracing performance and lack of a DLSS-like feature at launch – AMD is already working on its own AI-powered supersampling technology though. At the top of the Radeon RX 6000 series’ stack sits the flagship RX 6900 XT, the red company’s very own answer to NVIDIA’s king of the hill, the GeForce RTX 3090.
At first glance, it’s almost impossible to tell the difference between the RX 6900 XT and RX 6800 XT reference cards from AMD. In fact, there isn’t any between these two big hitters. Despite being regarded as the fastest graphics card that AMD has ever produced, the RX 6900 XT here is a like for like model of the RX 6800 XT. They even share the same standout features such as the Infinity Cache and Smart Access Memory, which I have already covered in my review of the RX 6800 XT (you can read about it here). Where they do differ is in their compute units (or CU). Where the RX 6800 XT has 72 CU, the 6900 XT comes with 80. AMD claims that the RX 6900 XT was able to increase the performance-per-watt by up to 65-percent when compared to the last-generation RDNA. In comparison, the RX 68000 XT’s generation-over-generation improvement stood at 54-percent.
| Radeon RX 6900 XT | Radeon RX 6800 XT | |
|---|---|---|
| GPU | Navi 21 XT | Navi 21 XT |
| Compute Units | 80 | 72 |
| Boost Clock | 2,250Mhz | 2,250Mhz |
| VRAM | 16GB GDDR6 | 16GB GDDR6 |
| Memory Bus | 256-bit | 256-bit |
| Memory Speed | 16Gbps | 16Gbps |
| Price | US$999 | US$649 |
Now, you would expect that the claimed increased in performance would also mean a simultaneous increase in power consumption. AMD recommended a PSU of 750W for the RX 6800 XT whereas the 6900 XT will require 850W. Here’s where it’s really odd though; AMD has also rated both cards with the same 300W TDP (Thermal Design Power). It is quite intriguing how AMD managed to extract additional performance without jacking up power consumption or a bigger heat dissipation solution with the RX 6900 XT.
Oh, and one more key difference. While the RX 6800 XT costs US$649, the RX 6900 XT requires you to hand over US$999. That is a massive ask, even if it’s still a lot lesser than the GeForce RTX 3090 Founders Edition at US$1,499.
Curious to find out how the Radeon RX 6900 XT performs? Let’s find out.
Benchmark Setup
To keep our results consistent with past graphics cards benchmarks, I have stuck with the following usual specifications:
- AMD Ryzen 9 5900X CPU
- MSI MEG X570 Godlike
- Samsung 980 Pro 1TB SSD
- Windows 10 Home 64-bit
- ASUS ROG Swift PG43UQ 4K Gaming Monitor
Since AMD has openly pitted the RX 6900 XT against NVIDIA’s behemoth (literally) GeForce RTX 3090, I’ve pulled out our Founders Edition and put it to pace again with the latest GeForce ForceWare driver version 457.51 (at this point of writing). For comparison’s sake, I’ve also included the Radeon RX 6800 XT for good measure.
Games used for benchmarking
Here’s a list of the tool and games that I’ve chosen to benchmark all cards. The game genres were purposely varied to give us a sense of how the cards perform across a wide range of titles: shooters, action, strategy games, etc.
- 3DMark (Synthetic Benchmark)
- Shadow of the Tomb Raider
- Total War: Three Kingdoms (Battle)
- Wolfenstein: Youngblood
- Deus Ex: Mankind Divided
- Metro: Exodus
- Tom Clancy’s The Division 2
- Watch Dogs: Legion
- Call of Duty: Black Ops Cold War
- Gears 5
- Control
3DMark
3DMark is a synthetic benchmark that tests graphics and computational performance at different resolutions, starting at 1080p and going all the way up to 4K. A series of two graphics test, one physics test, and then a combined test stresses your hardware in turn to assess its performance.
We see the Radeon RX 6900 XT trailing behind the GeForece RTX 3090 FE in both DirectX 12-based Time Spy tests, which to be honest, is not surprising. It’s the results in the Firestrike benchmarks, which tests both Radeon cards’ DirectX 11 capabilities that are more interesting, as we see the RTX 3090 FE falling behind both cards. It’s a repeat of the results between the RX 6800 XT and RTX 3080 Founders Edition, and it looks like the RX 6000 series cards just have better optimisations for the older API, despite modern games these days having ditched it in favour of DirectX 12.
A synthetic benchmark like 3DMark only tells one small part of the story though. Let’s look at some real-world game performances below.
1080p Benchmarks (Max Settings)
I’ve said it before, and I’ll say it again. I think it's a huge waste of money for any decent gamer to use the new generation of flagship gaming cards to run games at 1080p - there are more suitable cards like the mid-entry RTX 3070 or RTX 3060 Ti cards. Nevertheless, for the purpose of benchmarking let’s find out how the Radeon RX 6900 XT fares at this resolution.
The results do speak for themselves here and there are some interesting highlights. For one, it’s not surprising to see the RTX 3090 FE outperforming both cards in most games – but the gap isn’t much at 1080p. What’s eye-catchy, is how the RX 6900 XT (and even the RX 6800 XT) is outperforming the GeForce card in the two games, Watch Dog Legion and Call of Duty: Black Ops Cold War, that are heavily optimised for NVIDIA cards. It looks like some questionable driver optimisations are at play here. It’s also worth noting that the RX 6800 XT isn’t all that far behind its more powerful sibling here.
1440p Benchmarks (Max Settings)
As with the 1080p benchmarks, my 1440p tests also pushed graphics settings of each game title to the highest possible.
The results pretty much mirrored the results in the 1080p benchmarks although the margins that the Radeon card gained in the earlier tests have been narrowed. In short, you really can’t go wrong with the Radeon RX 6900 XT, or any of these cards for that matter, for 1440p gaming.
4K Benchmarks (Max Settings)
I have long concluded that with the entrance of the Radeon RX 6800 XT, AMD has finally entered the realm of 4K gaming proper. The RX 6900 XT then, is pretty much an extension of what the RX 6800 XT is already capable of.
Here we see the RX 6900 XT losing some rather significant ground to the RTX 3090 FE, with the former losing out at almost all the games here except for Call of Duty: Black Ops Cold War and Gears 5 – and just barely too. It’s not farfetched to claim that the GeForce RTX 3090 is still the dominant card for anything 4K and beyond.
Ray Tracing Benchmarks (Max Settings)
My choices of games for ray trace benchmarking are more limited, as not all games with ray tracing work with both AMD and NVIDIA’s DXR. For instance, Wolfenstein: Youngblood’s ray tracing is only available for NVIDIA RTX cards, while Shadow of the Tomb Raider supports both. Anyway, given what we have seen so far in the standard benchmarks, it’s no surprise to see NVIDIA maintaining its lead in ray tracing performance.
NVIDIA's dominance in ray tracing isn't that surprising. They have had a two-year head start against AMD, after all. Both companies also approaches ray tracing differently: AMD does it by loading dedicated ray-tracing accelerators to its cards, while NVIDIA powers it with custom RT cores that are already in its second generation. Perhaps, just perhaps, one method works better than the other?
Content Creation Benchmarks
Both AMD and NVIDIA have marketed their RX 6900 XT and GeForce RTX 3090 cards at content creators too. So, let us have a look at how the RX 6900 XT performs in today’s GPU-accelerated content creation and productivity software and let the results speak for themselves.
- LuxMark – OpenCL Rendering
- IndigoBench – Open CL Rendering
- Adobe Premiere Pro CC 2020 – Video Editing (PugetBench)
Another branch of content creation, especially for gamers/streamers, that is rapidly gaining traction is digital video editing as the proliferation of content sharing platforms and widely available editing tools have enabled them, everyone and anyone to be a content creator.
Conclusion
From the get-go, AMD comparing the RX 6900 XT against the GeForce RTX 3090 has proven problematic. Firstly, the RTX 3090 has more than double the VRAM of the RTX 3080. It also has a wider memory bus and 20-percent more shader cores. There’s a class difference and by virtue of that, performance difference as well, between it and its one-tier down RTX 3080 sibling. The RX 6900 XT, in contrast, only has eight more compute units or just 10-percent more shader cores than the RX 6800 XT. That’s it.
And the results from the benchmarks are telling, with the RTX 3090 FE delivering superior performance over the RX 6900 XT in content creation and professional workloads. Even the RX 6800 XT matches it very closely in gaming. While both the RTX 3090 and the RX 6900 XT aren’t quite what I would call the ideal cards for gaming purposes (seriously, stick to the RX 6800 XT or the RTX 3080 for that), at least the RTX 3090 offers some tangible improvements and benefits over the RTX 3080.
Don’t get me wrong. I think the Radeon RX 6900 XT is a great card on its own, but it fails to impress relative to the RX 6800 XT. Or even the RTX 3080, if you factor in better ray tracing and DLSS. The incremental performance in gaming and content creation simply do not justify the nearly 40-percent more in price tag.
Perhaps the right question to ask then, is if the RX 6900 XT works better as an alternative professional card to the RTX 3090. There might be some truth to that, as there are applications works better with AMD optimised drivers. The NX CAM software from Siemens PLM and Dassault Systems’ Solidworks 2020 come to mind. If you happen to use any one of this software, then the RX 6900 XT could prove to be the best affordable choice - short of a Radeon Pro level graphics card - for you, but again, the RX 6800 XT will still represent the better value for almost the exact same specifications.
Source : Hardwarezone
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