4K Ray Tracing Showdown: FSR vs. DLSS on the 7900 XTX & 4080

Direct Answer/Analysis

When pushing pixels at 4K with demanding ray tracing enabled, the architectural differences between the NVIDIA RTX 4080 and AMD RX 7900 XTX become starkly apparent. The RTX 4080 establishes a commanding lead, a result of its more mature and powerful 3rd-gen RT Cores and the significant advantage conferred by its exclusive DLSS 3 technology.

In raw, native 4K ray tracing performance (without upscaling), the RTX 4080 is consistently faster than the RX 7900 XTX across the board. In heavily path-traced games like Cyberpunk 2077 or Alan Wake 2, this lead can be substantial, often making the difference between a choppy experience and a borderline playable one.

The real game-changer is the upscaling technology. The RTX 4080’s ace is DLSS 3, a two-part system combining AI-powered Super Resolution (upscaling) and Frame Generation. Super Resolution provides excellent image quality that often rivals or even exceeds native rendering, while Frame Generation inserts AI-generated frames to dramatically boost FPS. This combination allows the RTX 4080 to deliver smooth, high-frame-rate 4K ray tracing in even the most demanding titles.

The RX 7900 XTX counters with AMD’s FidelityFX Super Resolution (FSR). As a spatial upscaler, FSR 2 provides a crucial performance uplift, making 4K ray tracing viable on the card. However, its image reconstruction is generally considered a step behind DLSS, sometimes resulting in more noticeable shimmering or fizzing on fine details. While AMD has introduced FSR 3 with Fluid Motion Frames to compete with DLSS Frame Generation, its adoption is slower and the quality of the generated frames is still being debated. In the current landscape, the RTX 4080's DLSS 3 implementation offers a more polished and widely supported solution for maximum performance.

Ultimately, the contest isn't close. The RTX 4080's superior hardware for ray tracing, combined with the more mature and visually impressive DLSS 3 technology, creates a significantly better 4K ray tracing experience than the RX 7900 XTX with FSR.

Pros & Cons

NVIDIA RTX 4080 with DLSS

• Pros:

  • Significantly higher raw ray tracing performance.
  • DLSS 3 Frame Generation provides massive, class-leading FPS gains.
  • Superior image quality from DLSS Super Resolution with better temporal stability.
  • Mature and widely adopted ecosystem for both DLSS and ray tracing.

• Cons:

  • DLSS technology is proprietary and locked to NVIDIA hardware.
  • Frame Generation, while boosting FPS, can add a small amount of input latency.

AMD RX 7900 XTX with FSR

• Pros:

  • FSR is an open standard, offering cross-vendor compatibility.
  • Delivers a necessary and substantial performance boost for 4K ray tracing.
  • Can be competitive in games with lighter RT implementations.

• Cons:

  • Noticeably trails the RTX 4080 in raw ray tracing throughput.
  • FSR 2 image quality is generally considered inferior to DLSS.
  • FSR 3 and Fluid Motion Frames adoption is currently less widespread than DLSS 3.

Verdict

For gamers who prioritize a no-compromise 4K ray tracing experience, the NVIDIA RTX 4080 is the definitive winner. Its potent combination of superior RT core performance and the mature, high-quality upscaling and frame generation of DLSS 3 provides a level of performance and visual fidelity that the AMD RX 7900 XTX and FSR combination cannot currently match in the most demanding scenarios. While the 7900 XTX is a capable card, its weakness in intensive ray tracing workloads makes the RTX 4080 the clear choice for the ultimate ray-traced eye candy at 4K.