AMD Radeon Pro W6800X Duo vs NVIDIA GeForce RTX 3090 Ti Comparison

AMD’s Radeon Pro W6800X Duo and NVIDIA’s GeForce RTX 3090 Ti represent opposite ends of the workstation and enthusiast spectrum, yet both target users who demand extreme compute throughput. The data shows a clear split: the W6800X Duo is a specialized Apple MPX-format board with a 96th percentile ranking, while the RTX 3090 Ti is a more conventional PCIe card sitting at the 95th percentile. Across the two shared benchmarks, the RTX 3090 Ti wins decisively, but the W6800X Duo’s massive 32 GB memory pool and RDNA 2 architecture serve a different workload profile. This analysis walks through the benchmark results, architectural divergence, and specification gaps to determine where each card excels.

Where Each One Wins

The head-to-head benchmark data gives NVIDIA a clean sweep. In Geekbench OpenCL, the RTX 3090 Ti scores 174,441 against the W6800X Duo’s 124,335, a delta of –28.7% for AMD. The Vulkan gap is even larger: 215,633 versus 125,622, a –41.7% difference. These are not marginal leads; the RTX 3090 Ti outperforms the AMD card by roughly 40% in Vulkan and nearly 29% in OpenCL. For raw compute throughput in cross-platform APIs, the NVIDIA card is the clear winner in this matchup.

However, the W6800X Duo’s wins are contextual rather than benchmark-based, as it records zero direct benchmark victories. Its advantage lies in memory capacity and platform integration. The card carries 32 GB of GDDR6 on a 256-bit bus, while the RTX 3090 Ti has 24 GB of GDDR6X on a 384-bit bus. The AMD card’s bandwidth is 512.0 GB/s versus 1.01 TB/s for NVIDIA, so the RTX 3090 Ti also dominates memory throughput. Where the W6800X Duo wins is in sheer capacity for datasets that exceed 24 GB — think large neural network training batches or massive 3D scenes — and in its Apple MPX bus interface, which is designed for Mac Pro systems rather than standard PC motherboards.

The average benchmark scores tell a similar story. The W6800X Duo averages 135,774 across all tests, while the RTX 3090 Ti averages 131,938. That places the AMD card 2.9% higher on average, despite losing both head-to-head tests. This is because the RTX 3090 Ti’s average includes a 3DMark Steel Nomad DX12 score of 5,741, which drags its aggregate down. The AMD card’s three benchmarks (Metal, OpenCL, Vulkan) are all in the 124,000–157,000 range, creating a higher floor. So while the RTX 3090 Ti wins every shared test, the W6800X Duo has better consistency across its available benchmark suite.

The Verdict

The data suggests two distinct buyers. For anyone running cross-platform compute workloads — OpenCL or Vulkan — the RTX 3090 Ti is the undisputed choice. Its Vulkan score is 71.6% higher than the W6800X Duo’s, and its OpenCL score is 40.3% higher. The NVIDIA card also offers 40.00 TFLOPS FP32 performance versus 15.11 TFLOPS for AMD, a 2.6x raw compute advantage. If the workload fits within 24 GB of memory and uses standard PCIe 4.0 x16, the RTX 3090 Ti delivers far more performance per frame of execution.

The W6800X Duo is for a narrower audience: Mac Pro owners who need 32 GB of memory in a single Apple MPX slot. Its 512.0 GB/s bandwidth is less than half the NVIDIA card’s 1.01 TB/s, and its FP32 throughput is 62% lower. But the extra 8 GB of memory is non-negotiable for certain workloads — rendering massive textures or training models that spill past 24 GB. The AMD card’s Metal benchmark score of 157,365 also suggests strong performance in Apple’s native graphics API, where the RTX 3090 Ti has no comparable data point. If the system is a Mac Pro and the workload is Metal-centric with high memory pressure, the W6800X Duo is the only viable choice in this comparison.

Head-to-Head Benchmarks

The Geekbench OpenCL test shows the RTX 3090 Ti at 174,441 against the W6800X Duo’s 124,335. That is a 50,106-point gap, translating to a –28.7% delta for AMD. The NVIDIA card’s advantage stems from its 10,752 shading units, 336 TMUs, and 84 RT cores, all running at a boost clock of 1860 MHz. The AMD card counters with 3,840 shading units, 240 TMUs, and 60 RT cores at a 1967 MHz boost, but the sheer parallelism of the GA102 chip overwhelms the RDNA 2 design in this workload.

Vulkan widens the gap further. The RTX 3090 Ti scores 215,633, while the W6800X Duo manages 125,622 — a –41.7% delta. This 90,011-point difference suggests that NVIDIA’s Ampere architecture handles Vulkan’s driver overhead and command processing more efficiently. The RTX 3090 Ti also has 336 tensor cores, which can accelerate certain compute tasks even in Vulkan, although the benchmark does not isolate those. The AMD card has no tensor cores, relying purely on shading units and RT cores for compute.

The 3DMark Steel Nomad DX12 test appears only for the RTX 3090 Ti, scoring 5,741. Without a W6800X Duo score for comparison, this result is standalone, but it indicates strong DirectX 12 Ultimate performance. The AMD card supports the same API (12 Ultimate, 12_2), but no head-to-head data exists for this test. The RTX 3090 Ti’s average score of 131,938 is pulled down by this 3DMark result, yet its two Geekbench scores are both substantially higher than the AMD card’s equivalents.

FAQ

Q: Which card has higher raw FP32 compute performance?

A: The RTX 3090 Ti delivers 40.00 TFLOPS FP32, while the W6800X Duo provides 15.11 TFLOPS — a 2.6x advantage for NVIDIA.

Q: Is the W6800X Duo’s memory advantage significant?

A: Yes, it has 32 GB of GDDR6 versus 24 GB of GDDR6X on the RTX 3090 Ti. However, the NVIDIA card’s bandwidth is 1.01 TB/s, roughly double the AMD card’s 512.0 GB/s.

Q: Which card performs better in Vulkan?

A: The RTX 3090 Ti scores 215,633 in Geekbench Vulkan, compared to 125,622 for the W6800X Duo — a 41.7% lead for NVIDIA.

Q: Do both cards support the same APIs?

A: Both support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The W6800X Duo additionally has a Geekbench Metal score of 157,365, while the RTX 3090 Ti has no Metal benchmark listed.

Q: What bus interface does each card use?

A: The W6800X Duo uses Apple MPX, while the RTX 3090 Ti uses PCIe 4.0 x16. This makes the AMD card exclusive to Mac Pro systems, whereas the NVIDIA card fits standard PC motherboards.

Q: Which card has a higher average benchmark score?

A: The W6800X Duo averages 135,774 across its three benchmarks, while the RTX 3090 Ti averages 131,938 across its three — a 2.9% difference in AMD’s favor, despite losing both shared tests.

Architecture Differences

The W6800X Duo is built on TSMC’s 7 nm process with a 520 mm² die containing 26,800 million transistors, yielding a transistor density of 51.5 million per mm². The RTX 3090 Ti uses Samsung’s 8 nm node with a larger 628 mm² die and 28,300 million transistors, but a lower density of 45.1 million per mm². The AMD chip, Navi 21, is based on RDNA 2.0 architecture, which emphasizes efficiency per watt and features 60 ray accelerators (RT cores) but no dedicated tensor cores. The NVIDIA chip, GA102, uses Ampere architecture with 84 RT cores and 336 tensor cores, enabling hardware-accelerated ray tracing and AI compute.

The memory subsystems diverge completely. AMD pairs 32 GB of GDDR6 with a 256-bit bus, while NVIDIA uses 24 GB of GDDR6X with a 384-bit bus. The RTX 3090 Ti’s memory clock is 1313 MHz (21 Gbps effective), producing 1.01 TB/s bandwidth; the W6800X Duo’s memory runs at 2000 MHz (16 Gbps effective), yielding 512.0 GB/s. The NVIDIA card’s wider bus and faster memory give it a 97% bandwidth advantage. The AMD card compensates with 8 GB more capacity, but at lower per-byte throughput.

Compute resources also differ starkly. The RTX 3090 Ti has 10,752 shading units, 336 TMUs, and 112 ROPs, with pixel rate of 208.3 GPixel/s and texture rate of 625.0 GTexel/s. The W6800X Duo has 3,840 shading units, 240 TMUs, and 96 ROPs, with pixel rate of 188.8 GPixel/s and texture rate of 472.1 GTexel/s. NVIDIA leads in every throughput metric, and its FP16 performance matches FP32 at 40.00 TFLOPS (1:1 ratio), while AMD’s FP16 is 30.21 TFLOPS (2:1 ratio), meaning it halves throughput for FP32 workloads.

Specification Differences

| Specification | AMD Radeon Pro W6800X Duo | NVIDIA GeForce RTX 3090 Ti |

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

| Process Node | 7 nm (TSMC) | 8 nm (Samsung) |

| Transistors | 26,800 million | 28,300 million |

| Die Size | 520 mm² | 628 mm² |

| Base Clock | 1800 MHz | 1560 MHz |

| Boost Clock | 1967 MHz | 1860 MHz |

| Memory Size | 32 GB GDDR6 | 24 GB GDDR6X |

| Memory Bus | 256 bit | 384 bit |

| Memory Bandwidth | 512.0 GB/s | 1.01 TB/s |

| Shading Units | 3840 | 10752 |

| TMUs | 240 | 336 |

| ROPs | 96 | 112 |

| RT Cores | 60 | 84 |

| Tensor Cores | None | 336 |

| FP32 Performance | 15.11 TFLOPS | 40.00 TFLOPS |

| FP16 Performance | 30.21 TFLOPS (2:1) | 40.00 TFLOPS (1:1) |

| TDP | 400 W | 450 W |

| Slot Width | Quad-slot | Triple-slot |

| Power Connectors | None listed | 1x 16-pin |

| Suggested PSU | 800 W | 850 W |

| Bus Interface | Apple MPX | PCIe 4.0 x16 |

| Display Outputs | 1x HDMI 2.1, 4x Thunderbolt | 1x HDMI 2.1, 3x DisplayPort 1.4a |

| Length | 267 mm | 336 mm |

| Height | 120 mm | 140 mm |

| Width | Not listed | 61 mm |

| Launch MSRP | 4,999 USD | 1,999 USD |

| Release Date | 2021-08-02 | 2022-01-26 |

The launch MSRP difference is stark — the W6800X Duo debuted at 4,999 USD, while the RTX 3090 Ti launched at 1,999 USD. Both cards are end-of-life, but the AMD part’s Apple MPX form factor and 32 GB memory justify its premium for Mac Pro users, whereas the RTX 3090 Ti offers far higher compute performance at a lower price point for standard PC builds. The RTX 3090 Ti also has a wider physical footprint (336 mm vs 267 mm length) and a triple-slot cooler versus the AMD card’s quad-slot design, though the AMD card lists no explicit power connector, relying on the MPX interface for power delivery.