AMD Instinct MI455X vs NVIDIA RTX PRO 5000 Blackwell Comparison

The Verdict

The recorded data positions these two accelerators in entirely separate operating envelopes. The AMD Instinct MI455X is a massive, specialized compute module with a 2300 W power envelope, a 2 nm process, and 432 GB of HBM4 memory, while the NVIDIA RTX PRO 5000 Blackwell is an active, dual-slot workstation card with a 300 W power envelope, a 5 nm process, and 48 GB of GDDR7. The database shows no overlapping benchmark scores for the two, as the MI455X has no recorded benchmark results, whereas the RTX PRO 5000 Blackwell holds an average benchmark score of 182109 and a percentile rank of 98 among all GPUs. For any workload requiring graphics output, API support, or standard workstation deployment, the NVIDIA card is the only option with recorded data. The MI455X, by contrast, targets a different compute segment entirely: its specifications indicate a device built around raw memory capacity and bandwidth, not rasterization or display. The data implies that buyers should select the AMD part for massive memory-bound compute tasks, and the NVIDIA part for any environment that needs a self-contained, actively cooled accelerator with established benchmark performance.

Architecture Differences

The MI455X uses the CDNA 5.0 architecture with the MI450 256CU chip, fabricated by TSMC on a 2 nm process. It integrates 320,000 million transistors on a 2990 mm² die, yielding a transistor density of 107.0M per mm². The NVIDIA RTX PRO 5000 Blackwell uses the Blackwell 2.0 architecture with the GB202 chip, also fabricated by TSMC but on a 5 nm process. It contains 92,200 million transistors on a 750 mm² die, for a density of 122.9M per mm². The MI455X has no shading units, texture mapping units, or render output units listed in the database; its texture rate is 2,457.6 GTexel/s and its pixel rate is 0 MPixel/s. The NVIDIA card has 14,080 shading units, 440 TMUs, 160 ROPs, 110 RT cores, and 440 tensor cores, with a texture rate of 1,045.9 GTexel/s and a pixel rate of 380.3 GPixel/s.

The memory subsystems diverge completely. The MI455X uses 432 GB of HBM4 on a 24576-bit bus, with a memory clock of 1900 MHz (7.6 Gbps effective) and bandwidth of 23.3 TB/s. The RTX PRO 5000 Blackwell uses 48 GB of GDDR7 on a 384-bit bus, with a memory clock of 1750 MHz (28 Gbps effective) and bandwidth of 1.34 TB/s. The MI455X has no display outputs, while the NVIDIA card provides 4x DisplayPort 2.1b. The AMD part lists no API support for DirectX, OpenGL, or Vulkan; the NVIDIA card supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The MI455X uses an EAM Module slot width with no power connectors and a suggested power supply of 2700 W; the NVIDIA card is dual-slot, uses a single 16-pin connector, and suggests a 700 W power supply. The bus interfaces differ as well: PCIe 6.0 x16 for AMD versus PCIe 5.0 x16 for NVIDIA.

Head-to-Head Benchmarks

Direct head-to-head benchmark comparisons are unavailable, as the head-to-head benchmark list in the database is empty. The MI455X has no benchmark entries at all, and its average benchmark score is recorded as 0, with a percentile rank of 50 among all GPUs. The RTX PRO 5000 Blackwell, however, has three recorded benchmark results. In 3DMark Steel Nomad DX12, it scores 9579.5. In Geekbench OpenCL, it scores 254116. In Geekbench Vulkan, it scores 282631. Its average benchmark score across these tests is 182109, placing it at the 98th percentile of all GPUs.

The nearest rivals for the RTX PRO 5000 Blackwell provide context for its performance. The NVIDIA A100 SXM4 80 GB has an average score of 183725, which is 0.9% higher than the RTX PRO 5000's average, meaning the RTX PRO 5000 trails that card by 0.9%. The NVIDIA RTX 5000 Ada Generation scores 184664, putting it 1.4% ahead of the RTX PRO 5000. The GeForce RTX 4090 D scores 178050, which is 2.3% behind the RTX PRO 5000, so the RTX PRO 5000 leads that card by 2.3%. The A100 SXM4 40 GB scores 187147, which is 2.7% ahead of the RTX PRO 5000. These delta values indicate that the RTX PRO 5000 sits in a tight competitive band, within roughly 3% of several established accelerators, neither dominating nor being dominated by its closest recorded competitors.

Because the MI455X has no benchmark scores, no direct percentage comparison between the two cards can be made from the database. The only measurable comparison is structural: the MI455X lists a peak FP32 throughput of 157.3 TFLOPS and matching FP16 throughput of 157.3 TFLOPS (1:1), while the RTX PRO 5000 lists 66.94 TFLOPS for both FP32 and FP16 (1:1). The AMD part also lists a much higher texture rate, 2,457.6 GTexel/s versus 1,045.9 GTexel/s. These figures suggest a large raw compute advantage for the MI455X, but the absence of benchmark scores means the database cannot confirm real-world performance.

FAQ

Q: Which card has a higher average benchmark score?

A: The RTX PRO 5000 Blackwell, with an average benchmark score of 182109 and a percentile rank of 98. The MI455X has an average benchmark score of 0 and a percentile rank of 50, with no recorded benchmark entries.

Q: How does the RTX PRO 5000 Blackwell compare to its nearest rivals?

A: It trails the A100 SXM4 80 GB by 0.9%, trails the RTX 5000 Ada Generation by 1.4%, leads the GeForce RTX 4090 D by 2.3%, and trails the A100 SXM4 40 GB by 2.7%.

Q: What memory configurations do the two cards use?

A: The MI455X uses 432 GB of HBM4 on a 24576-bit bus with 23.3 TB/s bandwidth. The RTX PRO 5000 Blackwell uses 48 GB of GDDR7 on a 384-bit bus with 1.34 TB/s bandwidth.

Q: Does the MI455X support display outputs or graphics APIs?

A: No. The MI455X has no display outputs and lists N/A for DirectX, OpenGL, and Vulkan. The RTX PRO 5000 Blackwell has 4x DisplayPort 2.1b and supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Q: What are the power and physical requirements for each card?

A: The MI455X has a 2300 W TDP, uses an EAM Module slot, has no power connectors, and requires a 2700 W suggested power supply. The RTX PRO 5000 Blackwell has a 300 W TDP, is dual-slot, uses one 16-pin connector, and requires a 700 W suggested power supply.

Q: Which card has higher raw compute specifications?

A: The MI455X lists 157.3 TFLOPS for both FP32 and FP16, versus 66.94 TFLOPS for both on the RTX PRO 5000. The MI455X also has a higher texture rate of 2,457.6 GTexel/s versus 1,045.9 GTexel/s.

Where Each One Wins

The RTX PRO 5000 Blackwell wins in every category where recorded performance data exists. It has three benchmark scores, an average score of 182109, and a 98th percentile ranking. It supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, and provides four DisplayPort 2.1b outputs, making it the only option for visual computing, workstation graphics, or any API-dependent workload. Its 300 W power envelope, dual-slot design, and 700 W suggested power supply allow it to operate in standard workstation configurations, and its 48 GB of GDDR7 memory with 1.34 TB/s bandwidth is sufficient for many professional workloads. Its active production status confirms availability.

The MI455X wins on raw hardware specifications. Its 432 GB of HBM4 memory dwarfs the NVIDIA card's 48 GB, and its 23.3 TB/s bandwidth is over 17 times higher. Its FP32 and FP16 throughput of 157.3 TFLOPS is more than double the NVIDIA card's 66.94 TFLOPS. Its texture rate of 2,457.6 GTexel/s exceeds the NVIDIA card's 1,045.9 GTexel/s. The 2 nm process and 320,000 million transistors indicate a design focused on maximum compute density and memory capacity. The MI455X also uses PCIe 6.0 x16, a newer bus interface than the NVIDIA card's PCIe 5.0 x16. The AMD card is the choice for massive memory-bound workloads, while the NVIDIA card is the choice for any task that requires graphics, API support, or validated benchmark performance.

Specification Differences

The database records no overlapping specifications between the two cards beyond manufacturer TSMC and memory clock in MHz. The MI455X uses a 2 nm process; the RTX PRO 5000 uses 5 nm. Transistor counts differ: 320,000 million for AMD versus 92,200 million for NVIDIA. Die size is 2990 mm² versus 750 mm². Transistor density is 107.0M per mm² versus 122.9M per mm². Base clocks are 1000 MHz versus 1740 MHz; boost clocks are 2400 MHz versus 2377 MHz. Memory clocks are 1900 MHz (7.6 Gbps effective) versus 1750 MHz (28 Gbps effective). Memory size is 432 GB versus 48 GB; memory type is HBM4 versus GDDR7; bus width is 24576 bit versus 384 bit; bandwidth is 23.3 TB/s versus 1.34 TB/s.

Shading units are 32768 versus 14080 (though the MI455X lists 0 ROPs and no RT or tensor cores, while NVIDIA lists 160 ROPs, 110 RT cores, and 440 tensor cores). Texture rate is 2,457.6 GTexel/s versus 1,045.9 GTexel/s. Pixel rate is 0 MPixel/s versus 380.3 GPixel/s. FP32 is 157.3 TFLOPS versus 66.94 TFLOPS; FP16 matches each card's FP32 at 1:1. TDP is 2300 W versus 300 W. Slot width is EAM Module versus dual-slot. Power connectors are none versus 1x 16-pin. Suggested PSU is 2700 W versus 700 W. Bus interface is PCIe 6.0 x16 versus PCIe 5.0 x16. Display outputs are none versus 4x DisplayPort 2.1b. API support is N/A for all three APIs versus DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4. The NVIDIA card has dimensions of 267 mm by 111 mm by 40 mm; the AMD card has no recorded dimensions. The NVIDIA card has an active production status and a launch MSRP of 5,099 USD; the AMD card has no recorded production status or launch MSRP.