AMD Radeon RX 7900 XTX: Powerful, but Lacking in Ray Tracing

AMD has finally lifted the NDA on RDNA3 reviews, and today the new cards officially go on sale. As expected, RX 7900 XTX puts up a serious fight against Nvidia’s RTX 4080 16GB, trading blows in everything aside from ray tracing. But Nvidia still holds the crown when it comes to ray tracing, so it almost seems reasonable that its GPU costs $200 more, now that we have the number. Still, the Radeon RX 7900 XTX delivers tremendous value for its $999 asking price, earning it an Editors’ Choice from our sister publication PCMag.

We’ve covered the Radeon RDNA3 cards in detail previously, but to summarize, it’s the company’s first chiplet-based GPU. This approach is contrary to Nvidia’s monolithic die, which is one huge slab of silicon. Connecting tiny chiplets is less expensive and allows for better yields, at the price of outright performance compared to a monolithic design.

This is AMD’s first GPU built on TSMC’s 5nm process, which is the same node used by Nvidia. Interestingly because it’s using chiplets, AMD only uses the 5nm node for the main compute die. The Memory Cache Dies that surround the main die are all built on TSMC’s 6nm process. This is similar to what Intel will be doing with its upcoming Meteor Lake CPU, which will combine different “tiles” from different processes.

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The Benchmarks

PCMag tested both new GPUs, the XTX and the less-expensive XT, using a build with a Core i9-12900K CPU, an Asus Z690 ROG Maximus Hero motherboard, and 32GB of Corsair Vengeance DDR5 running at 5600MHz. All settings were left at stock speeds for testing.

In synthetic tests, we can see the results are very close between the Radeons and the RTX 4080, with the 4090 way out in front. As expected, in other words. The sole victory is in Time Spy Extreme, where the XTX nudges the 4080 out of the way by a small margin. In Superposition the XTX edges out the 4080, though, with the XT landing on the other side. That’s also what was predicted; that the 4080 would land in between them in some scenarios. The RTX 4080 crushed both Radeons in Lexmark, however.

AMD promised big gains in ray tracing this generation, and it’s largely achieved those gains. For example in F1 22, the 7900 XTX holds between a 74 and 100 percent advantage over the Radeon 6800 XT, which is huge. This translated into a win for the XTX over the 4080 when FSR/DLSS was enabled on F1 22. With it disabled, the 4080 took the lead, but when it was turned on the XTX came out in front by seven to 10 percent. In Guardians of the Galaxy, however, something went sideways. FSR couldn’t be enabled due to a bug, leading to a brutal beatdown of the Radeons by the 4080.

In modern, AAA titles without ray tracing involved, the 7900 XTX either leads the RTX 4080 by small margins or they are very close. The biggest gap it could pull was in Far Cry 5, where it achieved a 12 percent lead over the RTX 4080. Overall though, it’s very, very close between these two GPUs.

When it comes to legacy games, all these GPUs can run them at insane frame rates. It’s doubtful that people who play these games would have the budget for one of these GPUs also, but it’s still interesting to see the results. Overall, once again it’s quite close. But generally speaking, Nvidia holds a small advantage here.

When it comes to power and thermals, we expected AMD to clean Nvidia’s clock, but that’s not the case. When put under a full load, the Radeon XTX runs at a chilly 58C but has audible fan noise. That is not the case with Nvidia’s beefy RTX 4080, which is a silent GPU. The XTX also pulled more watts overall for the entire system than the other GPUs, including the RTX 4090. Overall, this will go up on the board as a win for Nvidia. It turns out its Ada Lovelace architecture is darn efficient, and though its GPU’s coolers are massive, they work wonderfully.

The Verdict

Overall, there’s not really a clear winner here between the Radeons and the RTX 4080. All three GPUs have their own strengths and weaknesses. The Radeons are less expensive than the 4080, but can’t do ray tracing as well. They also are louder in operation too, so there’s no such thing as a free lunch (is there ever?). It was previously reported that Nvidia might lower the 4080’s price to compete with the RDNA3 cards, but now that the dust has settled, that seems unlikely. The reason is Nvidia doesn’t really need to; it still has advantages over AMD’s cards that some would say justify the higher pricing.

Proper credit to AMD, though, for delivering a card that’s neck-and-neck with Nvidia’s more expensive GPU. If you don’t care about ray tracing, either of the Radeons is a great deal. The partner boards will also be pushing clock speeds and power consumption a bit. They might even run as cool and quiet as Nvidia’s cards. So if you’re in the market, you should wait a bit to see what those numbers are like. Overall though, it’s a bit disappointing to not see a TKO in this battle. Still, at least there’s some very healthy competition between AMD and Nvidia once again.

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AMD Radeon RX 7900 XTX: Powerful, but Lacking in Ray Tracing

The Benchmarks

The Verdict

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