Our launch-day coverage of the Radeon RX 6800 series includes: Radeon RX 6800 XT Review
, Radeon RX 6800 Review
, AMD Smart Access Memory Review
AMD has achieved the unthinkable—they now have parity with NVIDIA. Just a few weeks ago, people thought NVIDIA was so far ahead that they couldn't be caught anymore. The new RDNA II architecture brings with it substantial improvements in every area, which made this achievement possible.
The Radeon RX 6800 XT is almost twice (!) as fast as the Radeon RX 5700 XT, quite a huge gain generation over generation. Now, these cards are of course at different price points, but they are the best AMD had at the time. Compared to NVIDIA's offerings, we see great results, too. The RX 6800 XT is just 6% behind the RTX 3080 and 25% faster than the RTX 2080 Ti and RTX 3070. Before AMD's announcement, I've heard people say "oh if AMD could only match 2080 Ti, it would be huge win for them." NVIDIA's fastest, the RTX 3090, is 16% faster than the RX 6800 XT, at much higher pricing. AMD has the RX 6900 XT ready for that, we'll know more details soon.
With these performance numbers, the Radeon RX 6800 XT is the perfect choice for 4K gaming at 60 FPS. It achieved that mark in nearly all titles in our test suite. Things are different once you turn on raytracing. Just like on NVIDIA, there's a hefty performance hit when running with the DirectX Raytracing API. We only tested two games so far, but it seems the loss in performance is bigger than on NVIDIA, who improved in that area with Ampere. Remember, this is AMD's first-generation raytracing implementation. Performance is still very respectable. I expected RT performance similar to Pascal cards, where RT is emulated in shaders. RX 6800 XT does much better than that—I'd say we will see performance roughly around RTX 2080 Ti levels, with big differences depending on the title. AMD has a clear advantage here because they provide the hardware for the new gaming consoles, which have raytracing as one of their new features. This means that game developers will optimize their games for this architecture's RT capabilities. What we've seen so far is that RT on consoles will be minimal, just some basic eye candy, but I'm sure developers will figure out new innovative ways in the coming years. NVIDIA is big on raytracing, and they have to be to keep their performance lead.
With Navi 21, AMD is introducing a new component to the gaming GPU world—an L3 cache is part of the Navi 21 GPU. While traditionally, the better use of the die area was to add more shading units, this is different, now that power and heat is a problem. A cache does use a lot of die area, but also consumes very little power, which makes it an excellent idea when power constrained. The nature of GPU workloads can also benefit from an L3 cache—I expect we'll see it added in all future generations, at various sizes. Our test results suggest that the efficiency of the L3 cache varies greatly between games and resolutions.
Over the years, I have criticized AMD almost every time for their cooler designs and their weak performance. Guess they listened. The Radeon RX 6800 XT comes with one of the best coolers I've ever seen. It runs cool, quiet, is fairly compact, and easy to disassemble. It's the first time we're seeing a triple-slot reference design from AMD—a change long overdue. This gives them so much more physical space to work with for cooler optimization. I measured 77°C under heavy gaming, with the hot spot reaching 98°C—a huge improvement over RX 5700 XT. AMD clarified that the hotspot is designed to operate at up to 110°C indefinitely, so plenty of headroom there. What's more impressive is that noise levels are almost whisper quiet. This is the quietest AMD reference design ever, I think. While the GeForce RTX 3080 Founders Edition uses a complicated cooling setup to achieve dual-slot capability with noise levels of 36 dBA, AMD gives you a much simpler design that is A LOT quieter at the same time, just 31 dBA. I also found the card remarkably easy to disassemble, the only gotcha is the carbon nanofiber thermal pad you have to dissolve and replace with thermal paste. Just like NVIDIA's GeForce 30 lineup, idle fan stop is part of the Radeon RX 6000, too; both reference designs will shut down their fans completely when the card is idle at the desktop or running productivity applications, and while Internet browsing.
The cornerstone for all these improvements is power efficiency. NVIDIA learned this with the GeForce GTX 480, AMD has learned it just now. It seems their primary design goal was bringing down energy consumption and the rest will follow. They improved energy efficiency by 50% against the first-generation RDNA architecture, which makes them more efficient than even NVIDIA Ampere. We measured an average power draw of just 280 W during our Metro Last Light power test, which is a mix of lighter and highly demanding scenes. That's why I picked it many years ago, because it highlights a GPU's ability to quickly react to load changes to conserve energy. We also tested the RX 6800 non-XT today, which is even more efficient than the XT in this review because it runs lower clocks at lower voltage, which drives up efficiency. Dear AMD, the engineers who came up with this efficiency deserve a medal.
I didn't think I would see the day AMD fixes its multi-monitor power consumption. Finally, the memory no longer runs at full speed in that scenario, which greatly reduces power, down to 7 W, which is now much better than NVIDIA. A weak point is media playback as it now runs memory at full speed, resulting in almost 50 W power consumption. This looks like a driver bug, though.
Much has been talked about VRAM size during NVIDIA's Ampere launch. The GeForce RTX 3080 has 10 GB VRAM, which I still think is plenty for today and the near future. Planning many years ahead with hardware purchases makes no sense, especially when it comes to VRAM—you'll run out of shading power long before memory becomes a problem. The GTX 1060 will not drive 4K, no matter if it has 3 or 6 GB. Game developers will certainly make use of the added memory capacity on the new consoles, we're talking 8 GB here, as a large portion of the console's total memory is used for the OS, game, and game data. I think I'd definitely be interested in an RX 6700 Series with just 8 GB VRAM, but more affordable pricing. On the other hand, AMD's card is cheaper than NVIDIA's product and has twice the VRAM, so there is really no reason to complain.
With the Radeon RX 6800 XT, AMD introduces a new method of automated overclocking called "Rage Mode," enabled in the Radeon Software. We ran our whole test suite with this setting. There is no magic here, Rage Mode is a separate profile for power limit and fan settings. The idea is nice—a hand-optimized overclocking profile that is guaranteed to be stable at all times because it follows the default voltage-frequency curve. On average, we measured a performance improvement of 1%, which is nice because it's free, but not even close to what manual overclocking can achieve, as we got over 9%.
Priced at $650, the Radeon RX 6800 XT is positioned similarly to NVIDIA's RTX 3080, which has an MSRP of $700. At that price point, the 6800 XT matches the 3080 almost exactly in performance per dollar. Both cards are great options for 4K gaming. The RTX 3080 has better RT performance, but the RX 6800 XT has the better and quieter cooler. Performance differences also vary wildly between titles, good that we have a lot of data for you. Everything NVIDIA offers is currently out of stock, so actual market prices are highly inflated and completely unrealistic. I think this will change in the coming weeks. Let's hope AMD has enough inventory available to celebrate this victory, the Radeon RX 6800 Series will fly off shelves.