AMD Radeon RX 6950 XT vs NVIDIA GeForce RTX 4090 Comparison

The NVIDIA GeForce RTX 4090 and AMD Radeon RX 6950 XT represent two distinct generations of flagship graphics hardware. The data shows a comprehensive victory for the RTX 4090, which wins all ten head-to-head benchmark comparisons against the RX 6950 XT. While the RX 6950 XT held the performance crown for AMD in its generation, the benchmark results indicate a significant generational leap for NVIDIA's Ada Lovelace architecture.

Head-to-Head Benchmarks

The most decisive margin appears in the 3DMark Steel Nomad DX12 test, where the RTX 4090 scores 9,223 points against the RX 6950 XT's 4,235 points. That translates to a 117.8% performance advantage, meaning the RTX 4090 more than doubles the AMD card's result in this modern DirectX 12 workload. This is the single largest delta in the entire comparison and underscores how far ahead the newer architecture is in compute-heavy scenarios.

Compute performance tells a similar story. In the Passmark GPU Compute test, the RTX 4090 delivers 26,613 points versus 14,199 points for the RX 6950 XT, a difference of 87.4%. This near-doubling of compute throughput aligns with the raw FP32 specifications, where the RTX 4090 offers 82.58 TFLOPS compared to 23.65 TFLOPS for the RX 6950 XT. The Geekbench OpenCL results also favor NVIDIA, with the RTX 4090 scoring 255,416 against 205,998, a 24% lead.

Vulkan performance shows a substantial gap as well. The RTX 4090 achieves 271,631 in Geekbench Vulkan, while the RX 6950 XT manages 165,212. That 64.4% delta indicates that the RTX 4090 is not just faster in proprietary or legacy APIs but also excels in cross-platform graphics workloads. In the Passmark G3D test, which is a broader measure of graphics capability, the RTX 4090 scores 38,194 versus 28,070, a 36.1% advantage.

The legacy DirectX benchmarks follow the same pattern. In Passmark DirectX 10, the RTX 4090 leads by 36.6% (224 vs. 164). DirectX 12 shows a 31.6% edge (150 vs. 114), while DirectX 9 sees a 31% difference (397 vs. 303). Even the DirectX 11 result, which is the closest margin of any test, still favors the RTX 4090 by 8.7% (326 vs. 300). The 2D graphics test, Passmark G2D, also goes to NVIDIA with a 22.2% lead (1,299 vs. 1,063). Across all ten benchmarks, the RTX 4090 wins every single comparison, with margins ranging from 8.7% to 117.8%.

Architecture Differences

The fundamental architectural split is process node and chip design. The RTX 4090 uses the AD102 chip built on a 5 nm process at TSMC, while the RX 6950 XT uses the Navi 21 chip on a 7 nm process, also from TSMC. This node advantage contributes to the RTX 4090's transistor density of 125.3M per mm², which is more than double the RX 6950 XT's 51.5M per mm². In absolute terms, the AD102 packs 76,300 million transistors on a 609 mm² die, compared to 26,800 million transistors on a 520 mm² die for Navi 21.

The compute pipelines diverge sharply. The RTX 4090 features 16,384 shading units, 512 texture mapping units, and 176 ROPs. The RX 6950 XT counters with 5,120 shading units, 320 TMUs, and 128 ROPs. Ray tracing hardware also differs, with the RTX 4090 carrying 128 RT cores while the RX 6950 XT has 80. NVIDIA further adds 512 tensor cores to the RTX 4090, a feature entirely absent from the RX 6950 XT, which has no tensor core equivalent.

Clock speeds tell a nuanced story. The RTX 4090 has a base clock of 2235 MHz and a boost clock of 2520 MHz. The RX 6950 XT runs a base clock of 1860 MHz, a game clock of 2100 MHz, and a boost clock of 2310 MHz. While the AMD card's boost clock is only 210 MHz lower than the RTX 4090's, the sheer difference in shading unit count overwhelms any clock speed parity. Memory architecture also differs fundamentally: the RTX 4090 uses 24 GB of GDDR6X on a 384-bit bus, yielding 1.01 TB/s of bandwidth. The RX 6950 XT uses 16 GB of GDDR6 on a 256-bit bus, providing 576.0 GB/s.

FAQ

Q: Does the RTX 4090 win every benchmark against the RX 6950 XT?

A: Yes. The head-to-head data shows the RTX 4090 winning all ten tests, with deltas from 8.7% in Passmark DirectX 11 to 117.8% in 3DMark Steel Nomad DX12.

Q: What is the biggest performance gap between the two cards?

A: The 3DMark Steel Nomad DX12 test shows the largest delta at 117.8%, with the RTX 4090 scoring 9,223 versus the RX 6950 XT's 4,235.

Q: How do the memory subsystems compare?

A: The RTX 4090 has 24 GB of GDDR6X on a 384-bit bus, delivering 1.01 TB/s bandwidth. The RX 6950 XT has 16 GB of GDDR6 on a 256-bit bus, delivering 576.0 GB/s.

Q: Which card has more shading units?

A: The RTX 4090 has 16,384 shading units, exactly three times more than the RX 6950 XT's 5,120 shading units.

Q: Do both cards support the same APIs?

A: Yes, both support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Q: What is the transistor count difference?

A: The RTX 4090 contains 76,300 million transistors versus 26,800 million for the RX 6950 XT, a difference of nearly 50 billion transistors.

Specification Differences

| Specification | NVIDIA GeForce RTX 4090 | AMD Radeon RX 6950 XT |

|---|---|---|

| Architecture | Ada Lovelace | RDNA 2.0 |

| Process Node | 5 nm | 7 nm |

| Transistors | 76,300 million | 26,800 million |

| Die Size | 609 mm² | 520 mm² |

| Transistor Density | 125.3M / mm² | 51.5M / mm² |

| Base Clock | 2235 MHz | 1860 MHz |

| Boost Clock | 2520 MHz | 2310 MHz |

| Game Clock | N/A | 2100 MHz |

| Memory Size | 24 GB | 16 GB |

| Memory Type | GDDR6X | GDDR6 |

| Memory Bus | 384 bit | 256 bit |

| Memory Bandwidth | 1.01 TB/s | 576.0 GB/s |

| Shading Units | 16384 | 5120 |

| TMUs | 512 | 320 |

| ROPs | 176 | 128 |

| RT Cores | 128 | 80 |

| Tensor Cores | 512 | N/A |

| Pixel Rate | 443.5 GPixel/s | 295.7 GPixel/s |

| Texture Rate | 1,290.2 GTexel/s | 739.2 GTexel/s |

| FP32 Performance | 82.58 TFLOPS | 23.65 TFLOPS |

| FP16 Performance | 82.58 TFLOPS (1:1) | 47.31 TFLOPS (2:1) |

| TDP | 450 W | 335 W |

| Power Connectors | 1x 16-pin | 2x 8-pin |

| Suggested PSU | 850 W | 700 W |

| Display Outputs | 1x HDMI 2.1, 3x DisplayPort 1.4a | 1x HDMI 2.1, 2x DisplayPort 1.4a |

| Length | 304 mm | 267 mm |

| Height | 137 mm | 120 mm |

| Width | 61 mm | 50 mm |

| Release Date | 2022-09-19 | 2022-05-09 |

Where Each One Wins

The RTX 4090 is the clear winner across every single benchmark category in this comparison. Its most dominant victories come in modern, compute-intensive workloads. The 117.8% lead in 3DMark Steel Nomad DX12 and the 87.4% edge in Passmark GPU Compute indicate that this card is built for heavy rendering, ray tracing, and compute tasks that leverage large numbers of parallel processors. The 64.4% advantage in Vulkan also suggests strong performance in cross-platform games and applications that use this modern API. For anyone targeting maximum performance in DirectX 12 Ultimate titles or GPU-accelerated compute, the data points decisively to the RTX 4090.

The RX 6950 XT, while losing every head-to-head test, still holds relevance in specific contexts. Its smallest deficit is 8.7% in Passmark DirectX 11, showing that in legacy API workloads, the gap narrows considerably. The card's lower TDP of 335 W versus 450 W means it draws less power, though the suggested PSU of 700 W versus 850 W also reflects a lower system requirement. Its physical dimensions are smaller—267 mm length versus 304 mm—making it easier to fit in compact cases. The RX 6950 XT also uses two standard 8-pin power connectors rather than the single 16-pin connector required by the RTX 4090, which may simplify power cabling for some systems. For users prioritizing these practical considerations over raw benchmark scores, the RX 6950 XT remains a viable option, but the performance data shows no scenario where it outpaces the RTX 4090.