AMD Radeon PRO W6400 vs NVIDIA A2 Comparison

The AMD Radeon PRO W6400 and NVIDIA A2 are both single-slot, low-power workstation cards, but they target fundamentally different workloads. The W6400 is a display-oriented GPU for conventional workstations, while the A2 is a server-focused accelerator without any display outputs. Benchmark data shows a near-total split: the NVIDIA A2 edges ahead in OpenCL compute, while the AMD card dominates in Vulkan performance, creating a choice defined by software ecosystem and physical deployment rather than raw capability alone.

FAQ

Q: Which card is faster in Geekbench OpenCL?

A: The NVIDIA A2 wins the OpenCL test with a score of 35,357, which is 0.9% higher than the AMD Radeon PRO W6400’s 35,027. This is a marginal victory, placing both cards within the same performance tier.

Q: How large is the Vulkan performance gap?

A: The AMD Radeon PRO W6400 scores 39,286 in Geekbench Vulkan, which is 15.5% ahead of the NVIDIA A2’s 34,023. This is the largest performance difference in any benchmark between the two cards.

Q: Which GPU has more memory capacity?

A: The NVIDIA A2 has 16 GB of GDDR6 memory, which is four times the 4 GB found on the AMD Radeon PRO W6400. The A2 also has a wider 128-bit memory bus and higher bandwidth at 200.1 GB/s versus 128.0 GB/s.

Q: Can the NVIDIA A2 drive a display?

A: No. The NVIDIA A2 has “No outputs” listed for display outputs, making it unsuitable for direct monitor connection. The AMD Radeon PRO W6400 includes 2x DisplayPort 1.4a outputs.

Q: What is the thermal design power difference?

A: The AMD Radeon PRO W6400 has a TDP of 50 W, while the NVIDIA A2 is rated at 60 W. Both are single-slot cards with no external power connectors, and both recommend a 250 W system power supply.

Q: How do their average benchmark scores compare to their closest rivals?

A: The AMD card’s average benchmark score is 37,157, which sits 0.9% below the AMD Radeon RX Vega 56 and 1.7% above the NVIDIA GeForce GTX TITAN X. The NVIDIA A2’s average of 34,690 is 0.4% above the NVIDIA T1000 8 GB and 1.4% above the NVIDIA RTX A1000.

Architecture Differences

The two GPUs come from different architectural families and foundries. The AMD Radeon PRO W6400 uses the Navi 24 chip built on RDNA 2.0 architecture, manufactured by TSMC on a 6 nm process. The NVIDIA A2 uses the GA107 chip based on Ampere architecture, produced by Samsung on an 8 nm node. This process advantage gives AMD a higher transistor density: the W6400 packs 50.5 million transistors per mm² across a 107 mm² die, totaling 5,400 million transistors. The A2’s 8,700 million transistors are spread across a 200 mm² die, yielding a lower 43.5M / mm² density.

Core composition differs significantly. The AMD card has 768 shading units, 48 texture mapping units, and 32 ROPs, plus 12 ray tracing cores. The NVIDIA A2 has 1,280 shading units, 40 TMUs, and 32 ROPs, with 10 ray tracing cores and 40 tensor cores. The A2’s shading unit advantage is partially offset by its lower clock speeds — base 1440 MHz and boost 1770 MHz compared to the W6400’s 2039 MHz base and 2321 MHz boost. Memory architecture also diverges: the W6400 uses a 64-bit bus with 4 GB GDDR6 at 128.0 GB/s, while the A2 uses a 128-bit bus with 16 GB GDDR6 at 200.1 GB/s.

Feature sets show both support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The presence of tensor cores on the A2 is a notable differentiator, enabling AI inference workloads that the AMD card cannot accelerate through dedicated hardware. The A2’s PCIe 4.0 x8 interface provides double the lane width of the W6400’s PCIe 4.0 x4, which matters for data transfer in server environments. The W6400’s display outputs versus the A2’s lack thereof further underscore their divergent roles.

Where Each One Wins

The NVIDIA A2 wins in OpenCL compute, scoring 35,357 versus 35,027, a 0.9% advantage. This makes it the better choice for general-purpose GPU compute tasks that rely on OpenCL, such as scientific simulations or data processing. Its 16 GB memory capacity and 200.1 GB/s bandwidth provide substantial headroom for large datasets that would overflow the AMD card’s 4 GB frame buffer. The tensor cores also give the A2 a dedicated hardware path for AI inference, which is absent on the Radeon PRO W6400.

The AMD Radeon PRO W6400 wins decisively in Vulkan, scoring 39,286 versus 34,023, a 15.5% lead. This suggests superior performance in graphics-heavy workloads that use the Vulkan API, such as real-time rendering or certain game engines. The W6400’s higher clock speeds — boost 2321 MHz versus 1770 MHz — and its higher pixel rate of 74.27 GPixel/s versus 56.64 GPixel/s contribute to this advantage. Its display outputs make it the only one of the two that can directly drive monitors for visual output.

For workstation use cases requiring a physical display, the W6400 is the only viable option. For headless server deployments where compute or AI inference is the priority, the A2’s larger memory, tensor cores, and wider memory bus give it the edge. The A2’s predecessor being Quadro Turing and its successor being Workstation Ada indicate NVIDIA positions it within a server accelerator lineage. The W6400’s predecessor is Radeon Pro Vega, placing it in AMD’s traditional workstation graphics line.

Specification Differences

| Specification | AMD Radeon PRO W6400 | NVIDIA A2 |

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

| Architecture | RDNA 2.0 | Ampere |

| Process Node | 6 nm | 8 nm |

| Transistors | 5,400 million | 8,700 million |

| Die Size | 107 mm² | 200 mm² |

| Transistor Density | 50.5M / mm² | 43.5M / mm² |

| Base Clock | 2039 MHz | 1440 MHz |

| Boost Clock | 2321 MHz | 1770 MHz |

| Memory Clock | 2000 MHz (16 Gbps effective) | 1563 MHz (12.5 Gbps effective) |

| Memory Size | 4 GB | 16 GB |

| Memory Bus Width | 64 bit | 128 bit |

| Memory Bandwidth | 128.0 GB/s | 200.1 GB/s |

| Shading Units | 768 | 1280 |

| TMUs | 48 | 40 |

| ROPs | 32 | 32 |

| RT Cores | 12 | 10 |

| Tensor Cores | None | 40 |

| Pixel Rate | 74.27 GPixel/s | 56.64 GPixel/s |

| Texture Rate | 111.4 GTexel/s | 70.80 GTexel/s |

| FP32 Performance | 3.565 TFLOPS | 4.531 TFLOPS |

| FP16 Performance | 7.130 TFLOPS (2:1) | 4.531 TFLOPS (1:1) |

| TDP | 50 W | 60 W |

| Bus Interface | PCIe 4.0 x4 | PCIe 4.0 x8 |

| Display Outputs | 2x DisplayPort 1.4a | No outputs |

Head-to-Head Benchmarks

The two benchmark results tell a story of specialization. In Geekbench OpenCL, the NVIDIA A2 achieves a score of 35,357, edging out the AMD Radeon PRO W6400’s 35,027 by 0.9%. This is a narrow win, well within the margin of noise for many workloads. The A2’s higher FP32 throughput of 4.531 TFLOPS versus 3.565 TFLOPS likely contributes to this result, as does its wider 128-bit memory bus. Yet the delta is small enough that real-world OpenCL applications may see negligible differences.

The Geekbench Vulkan test flips the script dramatically. The AMD Radeon PRO W6400 scores 39,286, which is 15.5% higher than the NVIDIA A2’s 34,023. This is a substantial margin that indicates a clear architectural advantage for AMD in Vulkan workloads. The W6400’s higher boost clock of 2321 MHz versus 1770 MHz and its superior pixel rate of 74.27 GPixel/s versus 56.64 GPixel/s likely drive this win. Its texture rate of 111.4 GTexel/s also far exceeds the A2’s 70.80 GTexel/s, which helps in graphics-heavy scenes.

Looking at the broader competitive landscape, the AMD card’s average benchmark score of 37,157 places it 0.9% behind the AMD Radeon RX Vega 56 and 1.3% behind both the NVIDIA Tesla P4 and GeForce RTX 4070, while sitting 1.7% ahead of the GeForce GTX TITAN X. The NVIDIA A2’s average score of 34,690 puts it 0.4% ahead of the NVIDIA T1000 8 GB and AMD Radeon HD 7970, 1% ahead of the NVIDIA TITAN V, and 1.4% ahead of the NVIDIA RTX A1000. These figures position both cards in the 79th-80th percentile of all GPUs, indicating they are mid-to-upper tier performers despite their low power envelopes.

The Vulkan delta of 15.5% is the single most decisive number in this comparison. It suggests that for any application leveraging Vulkan — particularly modern game engines or Vulkan-based compute — the AMD card is the stronger choice by a wide margin. Conversely, the OpenCL result, while favoring NVIDIA, is too close to call as a definitive advantage. The A2’s 16 GB memory capacity remains its strongest practical asset, allowing it to handle datasets that would exhaust the W6400’s 4 GB capacity entirely, regardless of raw compute scores.