AMD Radeon RX 7900 XTX Review

We’re about two months into the newest generation of graphics cards, and we now have AMD’s answer to Nvidia’s GeForce 40-series GPUs: the Radeon RX 7000 series. Team Red is starting this generation with a pair of cards, labeled the RX 7900 XTX and RX 7900 XT. But while only an X separates them on paper – along with $100 difference on their price tags – there’s more difference than just a few cores and clockspeeds. This review is focused specifically on the RX 7900 XTX (so be sure to check out my separate RX 7900 XT review for a look at that card as well) and I can say up front that it acquits itself well even in the face of Nvidia’s enormous advantage in ray tracing.

AMD Radeon RX 7900 XTX – Design and Features

AMD’s new GPUs are built on the RDNA 3 architecture using a new chiplet design – the first time such a design has been used in a gaming GPU. The RX 7900 XTX, priced at $999, has 96 RDNA 3 compute units, 24GB of GDDR6 memory, and a game/boost clock of 2.3/2.5 GHz. This amounts to an estimated 61 shader teraflops of compute power. Its most direct competitor this generation (so far) is the $1,199 GeForce RTX 4080 which, for comparison purposes, has 9,728 CUDA cores, 304 fourth-gen Tensor cores, and 76 third-gen RT cores, with a boost clock of 2.5 GHz. Of course, you can’t really make direct comparisons between different architectures, so those number differences don’t really mean much until we get to actual performance comparisons.

Visually, the RX 7900 XTX is an attractive if fairly basic card (there’s no RGB to speak of), with a bit of a Gundam-like black metal aesthetic with silver and red accents. It’s thick but not excessively so, measuring 287mm x 123mm and thankfully only taking up two slots – a relief after Nvidia’s embrace of three-slot monsters. It features a three-fan design for cooling, which I found to be noticeably louder in my tests than the RTX 4080 and RTX 4090. It isn’t as loud as, say, a gaming laptop blasting off at full force, but it was definitely noticeable and especially so compared to the whisper-quiet coolers of the RTX 40-series cards. Still, it kept temperatures in check – I measured a peak of 67C right at the beginning of benchmarking that settled back down to a steady 55C once the fans kicked on.

For connectivity, the 7900 XTX has a leg up over Nvidia, being the first GPU with the new DisplayPort 2.1 standard, which enables things like 4K with HDR at 120Hz or higher, without having to rely on compression. There aren’t any monitors or TVs that use this available yet – everything still uses DisplayPort 1.4 or HDMI 2.0/2.1 at this point – but it future-proofs the card to be compatible if and when those monitors start hitting the market. It has two of those ports, alongside a single HDMI 2.1a and a USB-C port w/DP 2.1 connectivity.

The RX 7900 XTX uses two 8-pin connectors for power, a welcome return to normalcy compared to Nvidia’s migration to the new 16-pin 12VHPWR connector, which has had some issues with melting. The card has a TDP of 355 watts, for which AMD recommends an 800W minimum power supply. This is a bit higher than the RTX 4080’s 320W TDP, but still less than the behemoth RTX 4090’s 450W power draw.

AMD Radeon RX 7900 XTX – Performance

Before we get into testing, I’ll quickly mention that we’re in the process of updating our GPU test rig, but weren’t able to complete the changeover in time for this review. Check back in the future once that build is complete, at which point we have plans to retest the new crop of graphics cards on the updated bench.

That said, our current test bench is no slouch – it was top of the line when we built it in 2020 in advance of the RTX 30-series graphics cards and should be plenty representative of many PCs in use today.

Starting with our synthetic benchmarks, the RX 7900 XTX performs quite well. While it falls short of the much more expensive RTX 4090, it beats the RTX 4080 by a small to moderate margin in both 3DMark Fire Strike Ultra and Unigine Heaven – a strong showing considering it costs $200 less.

However, Nvidia still reigns supreme in the ray tracing synthetics. Admittedly, AMD has a better showing here than usual, with a relatively respectable 47.9 fps in the 3DMark Ray Tracing test and a score of 12967 in 3DMark Port Royal. Those scores put it about on par with the RTX 3080 in terms of ray tracing performance, which is still a very good graphics card – but it did launch at $699 more than two years ago. Compared to Nvidia’s latest, AMD’s cards produce less than half the performance numbers with ray tracing enabled.

Moving on to real gaming performance, the RX 7900 XTX does quite well in traditional rasterization workloads, but still loses out when ray tracing is involved, or in games that benefit from DLSS. Most of our benchmarks are CPU-bound at 1080p and 1440p on these high-end cards, so there’s not a ton of interesting information to glean from those tests. Looking at 4K, though, gives us the clearest delineation between GPU performance levels, and in those tests the RX 7900 XTX beat the RTX 4080 once, matched it once, and lost twice.

Matching or beating a more expensive card is certainly impressive, but the losses when ray tracing and DLSS are in the picture can be quite painful, such as in Metro Exodus Enhanced Edition, where the 7900 XTX managed only 42 fps, just a tad more than half the score of the RTX 4080.

This next chart looks specifically at a few additional games just at 4K, and you can see how the 7900 series does well in rasterization-only games, but really falls when you factor in the gains provided by Nvidia’s tech.

While AMD doesn’t have DLSS, let alone Nvidia’s new “frame-generating” DLSS 3, it does have its own form of upscaling, known as FSR. To test this I spent some time in Cyberpunk 2077, which has the benefit of both DLSS 3 and FSR 2.1.

As you can see, both AMD and Nvidia’s cards must rely on some sort of upsampling tech, as none of their cards hit 60 fps – and only one even makes it to 30 – without the benefit of DLSS or FSR. AMD says that with FSR 2, Quality mode is meant to provide a similar or better than native image quality alongside a significant performance gain, and uses an input resolution of 1440p to upscale to 4K. Performance mode, on the other hand, targets a similar image quality as native for a large performance gain, going from a 1080p input upscaled to 4K. At a glance, I couldn’t tell much difference between Quality and Performance without putting the images side by side, but the difference in fps did make a considerable impact on smoothness of play.

The most interesting comparison to me here is DLSS On/Frame Generation Off, compared with FSR Performance mode. Here the RX 7900 XTX averages 57 fps which, while short of the desired 60 fps target, is still quite playable with a good experience. Of course, the RTX 4080 holds steady at 73 fps in the same test, and even gets a boost all the way up to 108 if you turn on Frame Generation.

My main takeaway from these tests is that while AMD has gained some ground on Nvidia, Team Green is still the obvious choice if your goal is the best image quality and performance on the latest and most demanding games.

Of course, I’m making these comparisons between two GPUs at different prices, so I’d be remiss if I didn’t bring performance per dollar into the equation. The RX 7900 XTX carries a $999 MSRP, versus $1,199 for the RTX 4080.

Dividing the fps scores of both cards by their relative MSRPs, we arrive at a “frames per dollar” score by which you can see the RX 7900 XTX is the clear winner (aside from in Metro Exodus, which as mentioned suffers from the burdens of ray tracing and the lack of DLSS on the AMD card). So if you’re working with a tighter budget, this could still be a totally viable option for your next PC.



source https://www.ign.com/articles/amd-radeon-rx-7900-xtx-review

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