AMD Radeon RX 6800 XT vs NVIDIA GeForce RTX 4080 Mobile Comparison

The Verdict

The data separates these two GPUs into distinct use cases. The AMD Radeon RX 6800 XT is the stronger all-around performer, winning 6 of 9 head-to-head benchmarks, while the NVIDIA GeForce RTX 4080 Mobile takes 3 wins. The RX 6800 XT holds a decisive edge in compute-heavy workloads, leading by 18.4% in Passmark GPU Compute, and it also wins in DirectX 11 (8.2%), DirectX 12 (4.2%), G2D (10.9%), and OpenCL (7.4%). The RTX 4080 Mobile counters with advantages in Vulkan (6.1%), DirectX 9 (7.3%), and a marginal DirectX 10 lead (1.3%).

For users prioritizing raw compute, legacy DirectX 11/12 gaming, and 2D acceleration, the RX 6800 XT is the clear choice. Its average benchmark score of 48477 places it at the 85th percentile of all GPUs, while the RTX 4080 Mobile sits at the 81st percentile with an average of 38135. The 27.1% gap in average scores is substantial, though the RTX 4080 Mobile’s lower power envelope (110 W vs 300 W) makes it the pick for mobile systems where thermal and battery constraints dominate. The RTX 4080 Mobile is also the better option for Vulkan-centric applications and older DirectX 9 titles, where it holds a 7.3% edge.

Architecture Differences

The two GPUs come from different manufacturing generations and design philosophies. The AMD Radeon RX 6800 XT uses the Navi 21 chip on RDNA 2.0 architecture, built on a 7 nm process at TSMC, with 26,800 million transistors on a 520 mm² die. The NVIDIA GeForce RTX 4080 Mobile employs the AD104 chip with Ada Lovelace architecture, fabricated on a 5 nm process, packing 35,800 million transistors into a smaller 294 mm² die. The transistor density tells the story: the RTX 4080 Mobile achieves 121.8M transistors per mm² versus 51.5M for the RX 6800 XT, reflecting the newer manufacturing node.

Memory configurations differ significantly. The RX 6800 XT offers 16 GB of GDDR6 on a 256-bit bus with 512.0 GB/s bandwidth and 16 Gbps effective memory clock. The RTX 4080 Mobile has 12 GB of GDDR6 on a narrower 192-bit bus, yielding 432.0 GB/s bandwidth and 18 Gbps effective clock. The RX 6800 XT’s wider bus provides 18.5% more bandwidth, which benefits high-resolution textures and compute workloads.

Compute unit counts favor NVIDIA in raw shader count: 7424 shading units versus 4608 for AMD, though the RX 6800 XT has more texture mapping units (288 vs 232) and more render output units (128 vs 80). Ray tracing hardware also differs: the RX 6800 XT has 72 RT cores, while the RTX 4080 Mobile has 58 RT cores plus 232 tensor cores, which the AMD part lacks entirely. This tensor core presence gives NVIDIA a hardware advantage for AI-accelerated features, though the benchmark data does not isolate that capability.

Clock speeds and power targets diverge sharply. The RX 6800 XT runs at 1825 MHz base, 2015 MHz game, and 2250 MHz boost, drawing 300 W. The RTX 4080 Mobile operates at 1290 MHz base and 1665 MHz boost, consuming only 110 W. This 190 W difference in TDP explains why the RX 6800 XT achieves higher pixel rate (288.0 GPixel/s vs 133.2 GPixel/s) and texture rate (648.0 GTexel/s vs 386.3 GTexel/s), despite the RTX 4080 Mobile having a higher FP32 throughput (24.72 TFLOPS vs 20.74 TFLOPS).

Head-to-Head Benchmarks

The largest margin in the entire comparison belongs to the RX 6800 XT in Passmark GPU Compute, where it scores 13245 against 11191, a 18.4% advantage. This indicates substantially better performance in general-purpose compute tasks, likely driven by the wider memory bus and higher clock speeds.

In Passmark G2D, the RX 6800 XT wins 1030 to 929, a 10.9% lead, reflecting its superior 2D acceleration capabilities. Passmark DirectX 11 shows the RX 6800 XT ahead by 8.2% (264 vs 244), and DirectX 12 sees a 4.2% edge (100 vs 96). The OpenCL test favors the RX 6800 XT by 7.4% (171304 vs 159575), reinforcing its compute strength.

The RTX 4080 Mobile’s wins are notable but narrower. In Geekbench Vulkan, it scores 145807 against 136875, a 6.1% advantage, suggesting stronger Vulkan API optimization. Passmark DirectX 9 shows a 7.3% lead (286 vs 265), which is the largest NVIDIA margin. The DirectX 10 result is essentially a tie at 157 vs 155, a 1.3% difference that falls within noise.

The closest contest is Passmark G3D, where the RX 6800 XT wins by a razor-thin 0.2% (24980 vs 24926). This near-parity in the overall 3D graphics score suggests that for general gaming, the two GPUs are effectively equivalent, with the RX 6800 XT’s advantages in specific API tests being offset by the RTX 4080 Mobile’s Vulkan and DirectX 9 strengths.

FAQ

Q: Which GPU has the higher average benchmark score?

A: The AMD Radeon RX 6800 XT scores 48477 on average, which is 27.1% higher than the NVIDIA GeForce RTX 4080 Mobile’s average of 38135.

Q: How do the two GPUs compare in compute performance?

A: The RX 6800 XT leads by 18.4% in Passmark GPU Compute (13245 vs 11191) and by 7.4% in Geekbench OpenCL (171304 vs 159575), indicating a clear compute advantage for AMD.

Q: Where does the RTX 4080 Mobile outperform the RX 6800 XT?

A: The RTX 4080 Mobile wins in Geekbench Vulkan by 6.1% (145807 vs 136875), in Passmark DirectX 9 by 7.3% (286 vs 265), and in Passmark DirectX 10 by 1.3% (157 vs 155).

Q: What is the memory bandwidth difference?

A: The RX 6800 XT provides 512.0 GB/s bandwidth on a 256-bit bus, while the RTX 4080 Mobile offers 432.0 GB/s on a 192-bit bus, giving AMD an 18.5% bandwidth advantage.

Q: How do power requirements differ?

A: The RX 6800 XT has a 300 W TDP and requires a 700 W power supply with 2x 8-pin connectors, while the RTX 4080 Mobile uses 110 W with no external power connectors, being an integrated graphics processor for laptops.

Q: Which GPU is better for DirectX 12 gaming?

A: The RX 6800 XT wins Passmark DirectX 12 by 4.2% (100 vs 96), though the overall Passmark G3D scores are nearly identical (24980 vs 24926), suggesting minimal real-world difference.

Where Each One Wins

The AMD Radeon RX 6800 XT dominates in compute scenarios. Its 18.4% lead in GPU compute and 7.4% advantage in OpenCL make it the superior choice for rendering, scientific calculations, and other non-gaming workloads. The 10.9% G2D advantage also makes it better for desktop applications and 2D-heavy tasks. In DirectX 11 and DirectX 12 gaming, the RX 6800 XT holds wins of 8.2% and 4.2% respectively, making it the preferred option for the majority of modern Windows titles.

The NVIDIA GeForce RTX 4080 Mobile excels in specific API environments. Its 6.1% Vulkan advantage suggests better performance in Vulkan-based games and applications, while the 7.3% DirectX 9 lead covers older titles. The RTX 4080 Mobile’s 110 W power draw makes it the only viable choice for thin-and-light laptops, where the RX 6800 XT’s 300 W requirement and dual-slot design are physically impossible. The RTX 4080 Mobile also benefits from 232 tensor cores, which the RX 6800 XT lacks entirely, potentially enabling AI features despite not being directly benchmarked here.

For overall gaming performance, the Passmark G3D scores show a 0.2% difference in favor of the RX 6800 XT, meaning gamers should choose based on API compatibility and system constraints rather than raw 3D performance. The RTX 4080 Mobile’s 12 GB memory is sufficient for most titles, but the RX 6800 XT’s 16 GB capacity and 18.5% higher bandwidth provide headroom for future high-resolution textures.

Specification Differences

The two GPUs differ on nearly every major specification. The RX 6800 XT uses a 7 nm process with 26,800 million transistors, while the RTX 4080 Mobile uses 5 nm with 35,800 million transistors. Die size is 520 mm² for AMD versus 294 mm² for NVIDIA. Clock speeds: the RX 6800 XT boosts to 2250 MHz, the RTX 4080 Mobile to 1665 MHz. Memory: 16 GB vs 12 GB, with bus widths of 256-bit vs 192-bit and bandwidth of 512.0 GB/s vs 432.0 GB/s.

Shading units favor NVIDIA at 7424 vs 4608, but AMD has more TMUs (288 vs 232) and ROPs (128 vs 80). Ray tracing cores: 72 for AMD, 58 for NVIDIA, with NVIDIA adding 232 tensor cores. Pixel rate is 288.0 GPixel/s for AMD versus 133.2 GPixel/s for NVIDIA, and texture rate is 648.0 GTexel/s versus 386.3 GTexel/s. FP32 performance is 20.74 TFLOPS for AMD and 24.72 TFLOPS for NVIDIA, though AMD’s FP16 reaches 41.47 TFLOPS (2:1) while NVIDIA’s FP16 stays at 24.72 TFLOPS (1:1).

Power and form factor: the RX 6800 XT draws 300 W with dual-slot cooling and 2x 8-pin connectors, requiring a 700 W PSU; the RTX 4080 Mobile is an integrated graphics processor at 110 W with no connectors. The RX 6800 XT is a 267 mm long, 120 mm tall, 50 mm wide card with 1x HDMI 2.1, 2x DisplayPort 1.4a, and 1x USB Type-C outputs; the RTX 4080 Mobile has portable-device-dependent outputs. The RX 6800 XT is end-of-life with a 649 USD launch MSRP from October 2020, while the RTX 4080 Mobile is active, released in January 2023, and has no listed launch MSRP. Both support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.