AMD RX 6800 XT and RX 6800 Review: AMD Finally Does Ray Tracing

AMD RX 6800 XT and RX 6800 Review: AMD Finally Does Ray Tracing

I was definitely excited when AMD announced all the specs and neat features of their 6000-series graphics cards at the end of October, albeit sceptical of what kind of ray tracing performance AMD’s latest GPUs would have. AMD was quiet about the ray tracing performance, and it could have been because its cards wouldn’t beat Nvidia 3000series cards. Unfortunately, that ended up being the case according to my testing. But don’t discount RDNA2 quite yet. While the ray tracing performance left me underwhelmed, that powerful base performance AMD boasted about? Both the RX 6800 XT and RX 6800 reviewed here matched or surpassed the RTX 3080 and RTX 3070 in nearly all the games I tested. These are still some seriously good GPUs.

Traditionally, the most important element of a new GPU is how many frames it can pump out. Yet with the addition of new features like Smart Access Memory and Rage Mode, what could have been two straight-forward graphics cards are way more complex. The strengths and weaknesses of the RX 6800 XT and RX 6800 have less to do with frames per second and more to do with what a person already has in their rig. If you find yourself agonizing over going team green or team red, oh man do I get it.

At its foundation, AMD has outdone itself with its new RDNA2 architecture, which powers its new generation of graphics cards. In addition to a 50% per watt performance increase over the previous generation, it’s added more compute units (CUs) and more shaders, and something called Infinity Cache: 128 MB of dedicated space to help optimise memory bandwidth and latency.

That 128 MB should keep all of the framebuffer, z-buffer, and most recent textures cached. Basically, important visual data that would normally be stored in the GPU’s VRAM gets moved over here, freeing up that space in the VRAM for other data to speed up rendering times.

In practice, I’m not sure if I noticed this while running gaming benchmarks or loading in from one scene to the next, but I did notice how quickly the image on my screen would reload when I switched from one resolution to the next. Normally, the screen goes black for a second or two while the GPU does what it needs to do, but that didn’t happen in some games. Switching screen resolutions on Shadow of the Tomb Raider, Assassins Creed Odyssey, and Control, for instance, was instantaneous. None of the black screen present with Nvidia’s RTX 3080 and RTX 3070 cards.

AMD Radeon RX 6800 XT and RX 6800

AMD Radeon RX 6800 XT and RX 6800

What is it?

AMD's newest discrete graphics cards with ray tracing

Price

RX 6800 XT: $1,049, RX 6800: $949

Like

Incredible base performance, cost, Smart Access Memory fps boost, compatible with most ray tracing games

No Like

Minuscule Rage Mode fps boost, some BIOS and game stability issues

For all of the benchmarks except for the Smart Access Memory comparisons, I used the following system with both the RX 6000 cards and both the RTX 3000 cards: Intel Core i9-10900K CPU; Asus ROG Maximus Extreme XII motherboard; 16 GB (8 GB x2) G.Skill Trident Z Royal DDR4-3600 DRAM; Samsung 970 Evo NVMe M.2 500GB SSD; Seasonic Focus GX-1000 PSU; and a Corsair H150i Pro RGB 360mm AIO for cooling. For the Smart Access Memory tests I swapped out the above CPU and motherboard for a Ryzen 9 5950X and an Asus ROG Crosshair VIII Hero motherboard.

But real quick, a note for all the testing that was done on that AMD motherboard: I could only set the RAM frequency to 3200 Hz, even though its top frequency is 3600 Hz. The latest BIOS for this motherboard currently has a glitch that prevents the system from booting if the DOCP preset profile is selected, which automatically overclocks your RAM to its maximum frequency. AMD is currently aware of this issue and is working to correct it, a spokesperson told me.

The previous BIOS version is fine, but the latest version is needed to use Smart Access Memory, so it was a bit of a Catch-22 with my testing. However, the lower frequency had little effect on performance as you’ll see in the charts with results from the AMD-configured system further down. I had zero issues with the Intel system.

Now, peep these charts:

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We don’t normally use 3DMark in our benchmark suite, but in this case it’s helpful as a starting point before getting into all the detailed gaming benchmarks. It’s incredible to see AMD have such a big lead over Nvidia, and it’s clear that AMD has improved on its Radeon cards immensely from its previous generation. It hasn’t really had such strong performance compared to Nvidia before, and the changes it made to its GPU architecture have clearly paid off.

As the gaming benchmarks below reflect, the RX 6800 XT outperforms the RTX 3080 and the RX 6800 outperforms the RTX 3070, but only without any fancy ray tracing effects. The RTX 3080 maintains a generous lead in the Port Royal tests, and the RTX 3070 is not too far behind the RX 6800 XT. The RX 6800’s ray tracing performance is sort of lacklustre, more akin to the performance of maybe the RTX 2080 or 2070 — pretty obvious once you start digging into individual games. The RX 6800 XT’s ray tracing performance is closer to the RTX 2080 Ti.

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AMD’s new GPUs generally match or exceed Nvidia’s new GPUs at 1440p and 4K. There are some outliers, like both RX 6000 cards can’t seem to out-perform the RTX 3000 cards in Control and Metro Exodus, but other than that performance is usually within 5 fps or a little more, and with Smart Access enabled, frame rates are off the charts — almost literally.

However, things start to get complicated when ray tracing and/or Smart Access is turned on. Theoretically, AMD’s new cards should be compatible with all current ray tracing enabled games, and they are for the most part. However, ray tracing will not work with a game like Wolfenstein: Youngblood because the ray tracing in that game is proprietary to Nvidia; the DLSS is integrated with the ray tracing, and since DLSS is Nvidia’s own frame rate-boosting, image sharping technology, AMD’s cards can’t use it. The option doesn’t even show up in the video settings.

AMD’s ray tracing works just fine in Control, Metro Exodus, Battlefield V, and any other game that separates the ray tracing setting from the DLSS setting. However, Control consistently froze with ray tracing enabled at 1440p and 4K with both graphics cards. I didn’t encounter any issues at 1080p. Even stranger, this issue was only present when I paired a Radeon card with an AMD processor. The problem was non-existent when I tested the same cards on my Intel system.

As for Smart Access Memory — it’s a new feature from AMD that allows a Ryzen CPU and a Radeon GPU to “talk” directly to each other and access each other’s memory without having to go through your system’s DRAM first. All that means that Smart Access Memory should improve game frame rates while locking you into an all AMD system. And it definitely works, but it also only works with certain games, just as Nvidia DLSS is only available in certain games too.

A game like Shadow of the Tomb Raider is compatible with both DLSS and Smart Access, but Smart Access does not offer a boost in Metro Exodus. If you’re wondering what games will benefit from that Smart Access, look for the huge AMD Ryzen/Radeon logo when the game first loads. That will usually indicate if that game will benefit from the new feature. Though not all the time.

Here are some charts so you can see what kind of performance boost to expect:

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Like enabling DLSS, Smart Access boosts the frame rate by about 10 fps. DLSS also enhances the visuals though, so technically it’s the better of the two. But again, just over 20 games support DLSS at the moment with more on the way next year. AMD will be introducing its own version of DLSS called Super Resolution, but that won’t be ready until next year as well. Sure, AMD has things like CAS (Contrast Aware Sharpening), but those don’t really boost frame rates in the same way that DLSS does, and not every game is compatible with those features. And if you’re wondering why I haven’t talked much about Rage Mode…well for starters, it’s only available on the RX 6800 XT and it doesn’t really give much of a performance boost, maybe one or two frames at the most.

So, the best way to give some games without DLSS a little performance boost without overclocking is with Smart Access — which means you will need to have an all-AMD system. But an all-AMD system means you’ll be missing out on ray tracing performance, which brings me to another round of charts. (I said there were going to be lots of charts, didn’t I?)

Nvidia still has the best ray tracing performance, and the RTX 3080 is still the best GPU to get if you want stunning graphics at 4K 60fps for around $1,000. And that makes sense since Nvidia is one generation ahead of AMD with regards to that feature. The RX 6800 XT is great for 1080p and 1440p ray tracing, just like the RTX 2080 Ti, but at least it cranks out the same stunning visuals as Nvidia’s cards.

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With ray tracing on, the RTX 3080 has a sizable lead over the RX 6800 XT, even with Smart Access Memory enabled. The RTX 3070 and RX 6800 are much closer in performance, but the 3070 still has about a 10-15 fps lead over the 6800. If you’ve already invested in a 4K monitor and several ray tracing games, it might make more sense for you to stick with Nvidia. But if you have only a 1440p monitor and/or not a lot a ray tracing games, AMD might make the most sense instead, especially if you’ve already invested in a new Ryzen 5000 series desktop processor.

That’s really the incentive though, isn’t it? In theory, it’s a good one too. That Smart Access fps boost that’s only capable when you pair an AMD GPU with an AMD CPU means better performance, ray tracing or not, although it’s limited to a few games and sometimes only certain resolutions in those games. Nvidia’s DLSS will give select games a performance boost at all resolutions and isn’t CPU dependent at all. But given that both the RX 6800 XT and RX 6800 get better base performance than the RTX 3080 and RTX 3070, it makes AMD’s new graphics cards the better deal — at least for the RX 6800 XT anyway, which is $1,049, or $80 less than the RTX 3080. It’s a harder argument for the $949 RX 6800, which is around $100 more than the RTX 3070. It does have better base performance, but I’m not sure it feels like $100 better base performance.

If you’re the kind of person who just wants to slap a GPU into your PC and call it a day, you can’t go wrong with either of AMD’s 6000 cards. Best base performance without doing anything? Solid deal. But the deeper you dive into ray tracing performance and BIOS-level performance boosts, these cards start to not look as sweet. I’m sure AMD will patch whatever bugs are bogging down the newest BIOS version, improve its Smart Access feature, and fix whatever the heck is happening with Control. But currently, Nvidia is still doing a better job on the software side of things. Unfortunately, that’s not enough of a difference for me to say Nvidia or AMD is better overall. Ultimately it comes down to if you’d be happy with one of these new AMD cards. I know I would be.

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  • Better base performance than Nvidia’s newest graphics cards.
  • Competitively priced for the performance and features.
  • Ray tracing performance is a little disappointing, but not awful for first-gen ray tracing cards.
  • AMD has some bugs to work out on the software side of things.