Tested: 5 key things you need to know about AMD’s Radeon RX 6900 XT
Don't have time to sift through endless benchmarking charts? Read this instead.
By Brad Chacos
PCWorldDec 8, 2020 6:00 am PST
Image: Brad Chacos/IDG
The Radeon RX 6900 XT is finally here, and it’s Team Red’s first enthusiast-class graphics card to hit the streets in a long, long time. AMD’s $1,000 GPU manages to meet or beat Nvidia’s monstrous GeForce RTX 3090 in many games for a whopping $500 less and stay quiet while doing it, but that doesn’t make this beast an automatic must-buy. Our RDNA 2 architecture explainer and comprehensive Radeon RX 6900 XT review wade deep into the details and benchmarks, but if you don’t have time to read thousands of words and parse dozens of performance graphs, here are five key things you need to know about AMD’s Radeon RX 6900 XT.
This is AMD’s first card to challenge Nvidia’s flagship GeForce offering in many, many moons, and it’s easy to see why the company released it: The Radeon RX 6900 XT smokes. Even with all the eye candy cranked to maximum in games, AMD’s card is fast enough to spit out enough frames to keep 4K displays and high refresh rate 1440p monitors fed very well. The $1,500 GeForce RTX 3090 is faster, yes—by 9.2 percent at 4K and a mere 2.2 percent at 1440p across our standard testing suite—but it costs a staggering $500 more. AMD also manages to beat the RTX 3090’s performance flat-out in select games on our system, including at 4K. (It also loses in some games by a considerable margin.)
If you want some of the absolute best 1440p gaming possible, the Radeon RX 6900 XT is worth considering, especially given the RTX 3090’s steep price premium.
Better yet, the Radeon RX 6900 XT can get even faster when paired with a Ryzen 5000 processor thanks to AMD’s Smart Access Memory technology. The uplift varies greatly depending on the game you’re playing, the resolution you’re playing at, and even the settings you use, but in our test suite, we saw performance increase in almost all cases, with several games gaining 5 to 8 percent more frames. Some games respond exceptionally well to Smart Access Memory, however. AMD claims Assassin’s Creed: Valhalla, Call of Duty Black Ops Cold War, Forza Horizon 4, and Red Dead Redemption 2 can see double-digit performance gains in the right circumstances. It’s a killer feature.
All that said, most gamers shouldn’t buy it. The step-down Radeon RX 6800 XT costs $350 less than the 6900 XT, but the 6900 XT is only 4.2 percent faster than the 6800 XT at 1440p resolution and 6.7 percent faster at 4K. Top-tier graphics cards like this offer terrible price-to-performance ratios, and the Radeon RX 6900 XT doesn’t offer a tangibly different experience than the 6800 XT despite its hefty 53 percent markup. The step-down card offers great 4K and high-refresh 1440p gaming experiences, too. We said the same thing about the GeForce RTX 3090 in comparison to the RTX 3080.
3. AMD needs a DLSS equivalent for ray tracing, stat
RDNA 2-based cards like the Radeon RX 6900 XT offer dedicated real-time ray tracing for the first time, and as the biggest “Big Navi” offering, the 6900 XT performs the best in AMD’s GPU lineup with the cutting-edge lighting effects active. That said, AMD’s first-gen implementation isn’t quite as potent as Nvidia’s more mature ray tracing hardware, and Radeon currently lacks an alternative to Nvidia’s fantastic DLSS 2.0 AI upscaling technology, which claws back many of the frames lost to ray tracing’s substantial performance impact. The company says it’s working on a more open feature dubbed “FidelityFX Super Resolution” that accomplishes similar tricks, but details remain not just scarce, but nonexistent.
Unfortunately, the lack of a DLSS alternative limits the Radeon RX 6900 XT to 1440p gaming with ray tracing active. Flipping ray tracing on at 4K tanks frame rates below the smooth 60 fps that PC gamers expect. We only tested a couple of games with less strenuous ray tracing effects as well. In games that load up with more extensive ray tracing effects—like Control, Minecraft RTX, or the drool-inducing Cyberpunk 2077—I wouldn’t be surprised if you’d need to be selective about what you activate even at 1440p. Hopefully AMD is pushing to get Super Resolution out as fast as possible.
4. The GeForce RTX 3090 might be a better option for you
AMD positions the Radeon RX 6900 XT as a take-no-prisoners gaming card. (Well, except for ray tracing I guess.) It comes awfully close to toppling the GeForce RTX 3090 and manages to beat it in several gaming scenarios. But you may want to spend $500 more for Nvidia’s card anyway.
If you’re a prosumer, Nvidia’s gargantuan 24GB of ultra-fast GDDR6X memory unlocks some 8K video and real-time editing capabilities you simply can’t achieve with other consumer graphics cards, though the Radeon RX 6900 XT’s 16GB of GDDR6 is no slouch and capable of 4K video workloads. Nvidia’s heavy investment into content creation tools are another significant advantage, as many popular software suites support CUDA and Optix optimizations devoted to speeding up performance on Nvidia hardware. As we covered in our GeForce RTX 3090 review, CUDA and Optix can drastically cut down the time it takes to complete workloads that embrace the technologies.
Deep-pocketed gamers who want the best gaming performance period may also opt for the GeForce RTX 3090. The Radeon RX 6900 XT hangs tough with Nvidia’s behemoth, sure, and it costs much less, but there’s no denying that the GeForce card is faster overall. Nvidia’s cards also hold that key ray-tracing advantage and can play ray-traced games at 4K, unlike AMD’s GPU. Again: Most people should buy a $650 Radeon RX 6800 XT or $700 GeForce RTX 3080. But if you want the fastest graphics card in the world, you need to pay the 3090’s daunting premium.
5. Custom versions could be badass
AMD says that custom versions of the Radeon RX 6900 XT are coming soon from partners like Sapphire, XFX, and Asus. Given what we know about the reference 6900 XT, those supercharged hotrods could push back even harder against the RTX 3090.
The luxurious, quiet reference card often lands within striking distance of the 3090 despite hitting warmer temperatures than all other enthusiast-class GPUs. The Radeon RX 6900 XT hits 83 degrees Celsius under load, while most other high-end GPUs top out in the 70s (and the 3090 runs at an ice-cold 68 degrees). Modern GPUs boost to faster speeds if there’s more power and thermal headroom available.
AMD also talked up the Radeon RX 6900 XT’s overclocking abilities to reviewers, touting its premium 14-layer PCB and 16-power-phase design. A large chunk of AMD’s reviewers guide was even devoted to explaining how to tune the graphics card manually, which I can’t recall seeing before. The Radeon RX 6800 XT usually has no problem overclocking to 2,500MHz or more in competent hands. AMD’s reviewers guide claims the company managed to push the reference cards to 2,750MHz in their labs—a huge increase over the rated 2,250MHz boost speed.
With all that in mind, imagine how far gigantic, heavily customized models of the Radeon RX 6900 XT could fly, with bespoke cooling solutions and hefty factory overclocks like we’ve seen in the XFX Merc 319 and Sapphire Nitro+ versions of the Radeon RX 6800 XT. Even a 4- or 5-percent uplift could be enough to topple the RTX 3090 more consistently, especially if you pair them with a new Ryzen 5000 CPU to tap into those sweet, sweet Smart Access Memory gains. Expect to hear more about custom Radeon RX 6900 XT models in the coming weeks, but don’t expect them to come cheap.