AMD challenges Nvidia’s RTX 4080 with its new RX 7900M laptop GPU

AMD is setting its sights on Nvidia’s RTX 4080 mobile GPU with the Radeon RX 7900M, the first laptop graphics chip to use a “chiplet” design and second-generation ray tracing as well.

AMD is working with Dell’s Alienware division to launch the chip as part of the Alienware m18 laptop, launching today. The laptop will be used to show off both the RX 7900M as well as the complementary, top-of-the-stack 7945HX processor, according to Priti Nagarajan, the AMD product manager in charge of the chip.

The RX 7900M is built upon the RDNA3 architecture, and is the complement to the Radeon RX 7900 desktop chip AMD launched in November 2022 — timed to undercut Nvidia’s RTX 40-series reveal. The same principle applies to how AMD sees the 7900M against Nvidia’s offerings. Obviously, the RX 7900M will differ from its desktop counterpart in price, but its fair to compare the two when it comes to other specifications.

Given the space constraints of a laptop, we’d expect the 7900M to fall a bit short of its desktop kin, and that appears to be the case. While the Radeon RX 7900 XTX desktop boasts 96 CUs running at 2.3GHz, and the 7900XT includes 84 CUs running at 2GHz, the mobile RX 7900M includes 72 CUs running at 1.825GHz, boosting up to 2.09GHz. Likewise, AMD’s desktop 7900 chips include either 24GB or 20GB of 384-bit GDDR6 memory; the RX7900M supports 16GB of GDDR6 memory running across a 256-bit memory interface.

AMD

AMD’s new mobile chip also boasts what it calls second-generation ray-tracing capabilities. It’s not exactly clear whether there’s a substantial difference over the improved ray tracing that debuted in the desktop version of the RX 7000 series, which included 1.5x more rays in flight. It’s likely to be the same, however. The RX 7900M chip includes AV1 encoding and decoding capabilities, the same as the desktop version.

There is an interesting twist, however. AMD recently announced FSR 3, the Radeon-specific rival to Nvidia’s DLSS 3. Both technologies work by “smoothing” frame rates to create a smoother visual experience. AMD’s portion of that, known as Fluid Motion Frames, has been confined to specific games, namely Immortals of Avenum and Forspoken. Now, according to Nagarajan, AMD is working to make the feature “global,” presumably to every game played on a supported Radeon GPU.

AMD is aiming the RX 7900M at “high refresh-rate 1440p gaming,” executives said.

AMD

On October 19, Dell will launch the Alienware m18, featuring an upgrade to the laptop that Alienware shipped earlier this year. The refreshed laptop will feature the Ryzen 9 7945HX (up from the 7845HX), the Radeon 7900M, and a larger 97Wh battery inside a larger 18-inch chassis. There will be two display options: an 18-inch 2560×1600 (165Hz) display, and an 18-inch 1920×1200 (480Hz) option. Dell has not released pricing.