AMD Instinct MI455X vs NVIDIA RTX PRO 2000 Blackwell Comparison

Where Each One Wins

The benchmark data splits these two accelerators into entirely different domains. The AMD Instinct MI455X records zero benchmark entries in the database, while the NVIDIA RTX PRO 2000 Blackwell carries a full suite of DirectX, OpenCL, Vulkan, and compute tests. That asymmetry alone defines the use-case separation. The MI455X is a compute-oriented accelerator with no display outputs and no graphics API support, making it unsuitable for workstation graphics work. The RTX PRO 2000 Blackwell, by contrast, posts scores across 3DMark Steel Nomad, Geekbench OpenCL and Vulkan, Passmark DirectX 9 through 12, and Passmark G2D and G3D tests, confirming its role as a general-purpose workstation GPU.

The NVIDIA part wins every category where data exists. Its 3DMark Steel Nomad DX12 score of 2374.5 indicates strong rasterization performance for a 70 W card. Passmark G3D at 20049 and Passmark GPU Compute at 8396 show balanced graphics and compute throughput. The Geekbench Vulkan score of 113865 and OpenCL score of 106087 demonstrate that the Blackwell architecture handles both graphics and general compute workloads effectively. The AMD MI455X, with its 2300 W thermal envelope and 432 GB of HBM4 memory, targets massive parallel compute workloads where graphics output is irrelevant. The absence of any benchmark scores for the MI455X in the database means the comparison is strictly theoretical for AMD, while NVIDIA's results are directly measurable.

For a builder choosing between these, the decision hinges on workload type. The RTX PRO 2000 Blackwell delivers measured, verified performance across standard workstation benchmarks. The MI455X offers raw specifications that suggest extreme compute capability, but no recorded benchmark results exist to confirm real-world behavior. The data favors the NVIDIA card for any task requiring graphics output, API support, or established performance metrics.

Architecture Differences

The two chips share a foundry but diverge sharply in every architectural choice. Both use TSMC fabrication, but the MI455X is built on a 2 nm process while the RTX PRO 2000 Blackwell uses 5 nm. The AMD chip, codenamed MI450 256CU, implements CDNA 5.0 architecture and contains 320,000 million transistors on a 2990 mm² die. The NVIDIA GB206 implements Blackwell 2.0 architecture with 21,900 million transistors on a 181 mm² die. Transistor density tells a nuanced story: AMD achieves 107.0M transistors per mm², while NVIDIA packs 121.0M per mm². Despite the AMD chip's massive scale, NVIDIA's smaller die achieves higher density.

The MI455X uses 32768 shading units with 1024 texture mapping units and zero ROPs. It has no dedicated ray tracing cores or tensor cores listed. The RTX PRO 2000 Blackwell uses 4352 shading units, 136 TMUs, 48 ROPs, 34 ray tracing cores, and 136 tensor cores. The AMD part reports no pixel rate and no texture rate figures for graphics work, consistent with its compute-only design. The NVIDIA card delivers 93.94 GPixel/s pixel rate and 266.2 GTexel/s texture rate.

Memory systems could not differ more. The MI455X carries 432 GB of HBM4 on a 24576-bit bus with 23.3 TB/s bandwidth. The RTX PRO 2000 Blackwell has 16 GB of GDDR7 on a 128-bit bus with 288.0 GB/s bandwidth. Clock speeds also diverge: the AMD chip runs 1000 MHz base and 2400 MHz boost, while the NVIDIA chip runs 982 MHz base and 1957 MHz boost. The MI455X's memory runs at 1900 MHz (7.6 Gbps effective), while the NVIDIA memory runs at 1125 MHz (18 Gbps effective).

The MI455X's FP32 and FP16 both rate 157.3 TFLOPS at a 1:1 ratio. The RTX PRO 2000 Blackwell rates 17.03 TFLOPS in both FP32 and FP16, also at 1:1. The AMD part's thermal design power is 2300 W with a suggested 2700 W power supply, while the NVIDIA part draws 70 W with a suggested 250 W PSU. Power delivery differs accordingly: the MI455X uses an EAM Module slot width with no power connectors, while the RTX PRO 2000 Blackwell is a dual-slot card with no power connectors either. The AMD card has no display outputs and no graphics API support. The NVIDIA card provides 4x mini-DisplayPort 2.1b outputs and supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

FAQ

Q: Which card has more memory bandwidth?

A: The AMD Instinct MI455X reports 23.3 TB/s of bandwidth from 432 GB of HBM4 on a 24576-bit bus. The NVIDIA RTX PRO 2000 Blackwell reports 288.0 GB/s from 16 GB of GDDR7 on a 128-bit bus.

Q: Can the MI455X run modern graphics APIs?

A: No. The MI455X lists DirectX, OpenGL, and Vulkan support as N/A, and it has no display outputs. The RTX PRO 2000 Blackwell supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4 with four mini-DisplayPort outputs.

Q: How do the thermal requirements compare?

A: The MI455X has a 2300 W TDP and suggests a 2700 W power supply. The RTX PRO 2000 Blackwell has a 70 W TDP and suggests a 250 W power supply.

Q: What benchmark data exists for the MI455X?

A: The database records no benchmark scores for the MI455X. Its average benchmark score is 0 and it has no nearest rivals. The RTX PRO 2000 Blackwell has ten recorded benchmark scores with an average of 25269.

Q: Which card has ray tracing hardware?

A: Only the NVIDIA RTX PRO 2000 Blackwell lists ray tracing cores (34) and tensor cores (136). The MI455X lists no dedicated RT or tensor core counts.

Q: How does the NVIDIA card compare to its nearest rivals?

A: The RTX PRO 2000 Blackwell scores 2% above the RTX A5000 Mobile, 1.4% below the AMD Radeon RX 6700M, 1.8% below the Radeon Pro W5700, and 1.8% below the GeForce RTX 3080 Ti Mobile.

Specification Differences

| Specification | AMD Instinct MI455X | NVIDIA RTX PRO 2000 Blackwell |

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

| Architecture | CDNA 5.0 | Blackwell 2.0 |

| Process node | 2 nm | 5 nm |

| Transistors | 320,000 million | 21,900 million |

| Die size | 2990 mm² | 181 mm² |

| Transistor density | 107.0M / mm² | 121.0M / mm² |

| Base clock | 1000 MHz | 982 MHz |

| Boost clock | 2400 MHz | 1957 MHz |

| Memory clock | 1900 MHz (7.6 Gbps) | 1125 MHz (18 Gbps) |

| Memory size | 432 GB | 16 GB |

| Memory type | HBM4 | GDDR7 |

| Memory bus | 24576 bit | 128 bit |

| Memory bandwidth | 23.3 TB/s | 288.0 GB/s |

| Shading units | 32768 | 4352 |

| TMUs | 1024 | 136 |

| ROPs | 0 | 48 |

| RT cores | None | 34 |

| Tensor cores | None | 136 |

| Pixel rate | 0 MPixel/s | 93.94 GPixel/s |

| Texture rate | 2457.6 GTexel/s | 266.2 GTexel/s |

| FP32 | 157.3 TFLOPS | 17.03 TFLOPS |

| FP16 | 157.3 TFLOPS (1:1) | 17.03 TFLOPS (1:1) |

| TDP | 2300 W | 70 W |

| Slot width | EAM Module | Dual-slot |

| Suggested PSU | 2700 W | 250 W |

| Bus interface | PCIe 6.0 x16 | PCIe 5.0 x8 |

| Display outputs | No outputs | 4x mini-DisplayPort 2.1b |

| DirectX | N/A | 12 Ultimate (12_2) |

| OpenGL | N/A | 4.6 |

| Vulkan | N/A | 1.4 |

| Dimensions | Not listed | 167 mm, 69 mm, 20 mm |

| Production status | Not listed | Active |

| Release date | 2026-07-22 | 2025-08-10 |

Head-to-Head Benchmarks

The database contains no head-to-head benchmark entries between these two cards, and the MI455X has no standalone benchmark scores. The comparison therefore relies entirely on the RTX PRO 2000 Blackwell's recorded results against the MI455X's absence of results. The NVIDIA card's strongest recorded scores come from compute and graphics tests. Its Geekbench Vulkan result of 113865 leads its OpenCL result of 106087 by about 7%, indicating the Vulkan path is slightly more efficient. The 3DMark Steel Nomad DX12 score of 2374.5 shows the card handles modern DirectX 12 workloads at a level consistent with its 70 W envelope.

Passmark results show a clear hierarchy within the NVIDIA card's own capabilities. Passmark G3D scores 20049, while Passmark GPU Compute scores 8396. DirectX 9 scores 241, DirectX 11 scores 174, DirectX 10 scores 122, and DirectX 12 scores 80. The G2D score of 1303 reflects basic 2D acceleration. These numbers indicate the RTX PRO 2000 Blackwell is strongest in general 3D rendering and compute, with legacy DirectX performance trailing modern workloads.

The nearest rival data places the RTX PRO 2000 Blackwell in a tight competitive band. It sits 2% above the RTX A5000 Mobile, which scores 24763. It sits 1.4% below the Radeon RX 6700M (25633), 1.8% below the Radeon Pro W5700 (25726), and 1.8% below the GeForce RTX 3080 Ti Mobile (25740). These deltas, all within roughly two percentage points, show the card performs essentially on par with a cluster of established mobile and workstation parts. The average benchmark score of 25269 places the card at the 70th percentile among all GPUs in the database.

For the MI455X, the percentile ranking of 50 with a zero average score reflects the complete lack of measured results. The 2300 W TDP and 432 GB memory configuration suggest a device built for scale-out compute deployments rather than desktop benchmarking. The absence of display outputs and graphics APIs reinforces that positioning. A buyer comparing these two cards must weigh verified NVIDIA results against unmeasured AMD specifications.

The Verdict

The data supports a straightforward selection based on workload. The NVIDIA RTX PRO 2000 Blackwell is the only card with recorded performance, and it delivers measurable results across graphics, compute, and API compatibility. Its 70 W TDP, dual-slot design, and 4x mini-DisplayPort outputs make it a practical workstation component. The 70th percentile ranking among all GPUs, with an average score of 25269, confirms it performs competitively against peer cards like the Radeon RX 6700M and GeForce RTX 3080 Ti Mobile, all within a 2% band.

The AMD Instinct MI455X presents a different proposition. Its specifications describe a device aimed at massive parallel compute: 157.3 TFLOPS in FP32, 432 GB of HBM4, and 23.3 TB/s of bandwidth. The 2300 W TDP and EAM Module form factor indicate installation in server racks, not workstation desks. The lack of display outputs and graphics API support means it cannot serve as a primary workstation GPU. No benchmark scores exist to validate real-world throughput, so any performance claim for the MI455X remains speculative.

The practical choice depends on the task. For standard workstation duties, the RTX PRO 2000 Blackwell delivers proven performance with modern API support and a compact physical footprint. For large-scale compute clusters where graphics output is irrelevant and raw throughput specifications matter more than measured results, the MI455X offers extreme memory capacity and compute density. The database records results for only one of these cards, and that card is the NVIDIA. Builders requiring verified performance should select the RTX PRO 2000 Blackwell. Builders with infrastructure capable of supporting a 2300 W accelerator and no need for display output can consider the MI455X, but they must accept the absence of benchmark validation.