AMD Instinct MI455X vs NVIDIA GeForce RTX 5090 D Comparison

Where Each One Wins

The AMD Instinct MI455X and NVIDIA GeForce RTX 5090 D occupy fundamentally different positions in the hardware landscape, and the recorded data makes the use-case split unusually clear. The MI455X is built around a 432 GB HBM4 memory subsystem with a 24576-bit bus and 23.3 TB/s of bandwidth, figures that dwarf anything in the consumer or workstation segment. The RTX 5090 D, by contrast, ships with 32 GB of GDDR7 on a 512-bit bus delivering 1.79 TB/s. That is a 13-fold difference in memory capacity and a 13-fold difference in bandwidth, both favoring the Instinct part. For workloads that scale with memory footprint or memory throughput, such as large language model inference, scientific simulation, or data-parallel compute kernels, the MI455X is the only viable option between the two.

The RTX 5090 D wins in every conventional graphics benchmark category. Its pixel rate of 423.6 GPixel/s, texture rate of 1,636.8 GTexel/s, and 176 ROPs give it a clear path to rasterization performance. The MI455X reports a pixel rate of 0 MPixel/s and 0 ROPs, which means it has no traditional display output path at all. The RTX 5090 D also includes 170 RT cores and 680 tensor cores, while the MI455X lists no RT or tensor core counts. For real-time rendering, ray tracing, or any workload that depends on the DirectX or Vulkan pipeline, the RTX 5090 D is the only part with functional support. The MI455X lists DirectX, OpenGL, and Vulkan as N/A, so any gaming or graphics application is simply outside its remit.

The benchmark wins are entirely one-sided because the MI455X has no recorded benchmark scores. The database shows zero benchmarks for the Instinct part, while the RTX 5090 D has ten recorded tests across 3DMark, Geekbench, and Passmark suites. The percentile scores reflect this: the MI455X sits at the 50th percentile among all GPUs, while the RTX 5090 D reaches the 92nd percentile. The average benchmark score for the MI455X is 0, whereas the RTX 5090 D averages 77,712 across its suite. The use-case split is therefore not about which part wins more tests, it is about which part can run the test at all. The MI455X is a compute accelerator with no graphics pipeline, while the RTX 5090 D is a complete graphics and compute solution.

Architecture Differences

The underlying silicon could hardly be more different. The MI455X uses the MI450 256CU chip built on CDNA 5.0 architecture, manufactured on a 2 nm process at TSMC. The RTX 5090 D uses the GB202 chip on Blackwell 2.0 architecture, also from TSMC but on a 5 nm node. The process node advantage for the Instinct part is clear: 2 nm versus 5 nm means significantly smaller transistors, which helps explain the transistor count disparity. The MI455X packs 320,000 million transistors on a 2990 mm² die, giving a density of 107.0 million transistors per square millimeter. The RTX 5090 D contains 92,200 million transistors on a 750 mm² die, with a higher density of 122.9 million per square millimeter. Despite the larger process node, the RTX 5090 D achieves higher transistor density, indicating a more compact logic design.

Clock behavior also diverges sharply. The MI455X has a base clock of 1000 MHz and a boost clock of 2400 MHz, while the RTX 5090 D runs at 2017 MHz base and 2407 MHz boost. The boost clocks are nearly identical, but the base clock difference of over 1000 MHz suggests the MI455X relies on aggressive boosting under load. Memory clocks differ as well: the MI455X runs at 1900 MHz with 7.6 Gbps effective data rate, while the RTX 5090 D runs at 1750 MHz with 28 Gbps effective. The GDDR7 on the RTX 5090 D has a much higher per-pin data rate, but the HBM4 on the MI455X achieves far greater aggregate bandwidth thanks to the massive bus width.

The shading resources are lopsided in opposite directions. The MI455X has 32,768 shading units and 1024 TMUs, producing a texture rate of 2,457.6 GTexel/s. The RTX 5090 D has 21,760 shading units and 680 TMUs, yielding 1,636.8 GTexel/s. In raw shader count and texture throughput, the MI455X leads by roughly 50 percent. Yet the RTX 5090 D has 176 ROPs and a pixel rate of 423.6 GPixel/s, while the MI455X has zero ROPs and zero pixel rate. This is not an oversight; the Instinct architecture omits the rasterization backend entirely. FP32 and FP16 compute also favor the MI455X at 157.3 TFLOPS for both precisions, versus 104.8 TFLOPS for the RTX 5090 D in both. The MI455X delivers 50 percent more floating-point throughput.

The power envelopes are extreme on both sides but for different reasons. The MI455X has a TDP of 2300 W with no power connectors listed and a suggested PSU of 2700 W. It uses an EAM Module slot width, meaning it is not a standard PCIe card form factor. The RTX 5090 D has a 575 W TDP with a single 16-pin connector and a suggested PSU of 950 W. It is a dual-slot card measuring 304 mm by 137 mm by 48 mm. The MI455X has no display outputs, while the RTX 5090 D includes 1x HDMI 2.1b and 3x DisplayPort 2.1b. The bus interfaces differ by one generation: PCIe 6.0 x16 for the Instinct part, PCIe 5.0 x16 for the GeForce.

Head-to-Head Benchmarks

Direct comparison is impossible because the MI455X has no recorded benchmark scores. The database shows zero benchmarks for the AMD part, and the head-to-head benchmark array is empty. The wins tally is 0 for the MI455X and 0 for the RTX 5090 D, because no common test exists. What the data does provide is a full benchmark profile for the RTX 5090 D, which can be interpreted against its nearest rivals.

The RTX 5090 D scores 14,326 in 3DMark Steel Nomad DX12, 310,674 in Geekbench OpenCL, and 376,915 in Geekbench Vulkan. In Passmark tests, it records 231 in DirectX 10, 371 in DirectX 11, 219 in DirectX 12, 434 in DirectX 9, 1,487 in G2D, 44,065 in G3D, and 28,396 in GPU compute. The average benchmark score is 77,712. The nearest rival data places the RTX 5090 D in a tight cluster: it sits 1.1 percent above the AMD Radeon RX 6650M XT (average score 76,904), 1.6 percent below the AMD Radeon RX 6850M XT (78,940), 2.1 percent below the NVIDIA Tesla P100 PCIe 12 GB (79,396), and 2.4 percent below the Tesla P100 PCIe 16 GB (79,605). These deltas are small, all within a few percentage points. The RTX 5090 D is not dramatically faster than these rivals in aggregate; it leads the RX 6650M XT by a slim margin and trails the other three by similarly narrow amounts.

The percentile data reinforces this picture. At the 92nd percentile among all GPUs, the RTX 5090 D sits high in the overall distribution, but its nearest rivals all cluster within the same performance band. The MI455X, at the 50th percentile with an average score of 0, cannot be compared on the same scale. The absence of benchmarks for the Instinct part means any head-to-head analysis must rely on architectural specifications rather than measured results. The recorded data shows no test where both parts have scores, so the only quantitative comparison available is the specification table.

The Verdict

The data supports a clear separation of roles. The AMD Instinct MI455X is a compute accelerator designed for memory-bound and throughput-bound workloads. Its 432 GB HBM4 memory, 23.3 TB/s bandwidth, 157.3 TFLOPS FP32/FP16, and 2,457.6 GTexel/s texture rate position it for large-scale data processing, AI training, and scientific computing. The absence of ROPs, display outputs, and graphics API support means it cannot render frames or drive a monitor. Any workload that requires rasterization, ray tracing, or a standard graphics pipeline must go to the RTX 5090 D.

The NVIDIA GeForce RTX 5090 D is the only part of the two with functional graphics capability. Its 176 ROPs, 423.6 GPixel/s pixel rate, 170 RT cores, 680 tensor cores, and full DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4 support make it a complete graphics solution. Its benchmark profile shows solid performance across all tested suites, with an average score of 77,712 and a 92nd percentile ranking. The compute side is weaker than the MI455X, with 104.8 TFLOPS FP32 and 1.79 TB/s bandwidth, but it remains competitive with its nearest rivals, all within 2.4 percent in either direction.

The verdict is straightforward. For high-bandwidth memory-intensive compute, the MI455X is the choice, provided the workload does not require graphics output. For any rendering, gaming, or general-purpose GPU workload that uses standard APIs, the RTX 5090 D is the only option between the two. The MI455X has no benchmark scores to support a performance claim, so its case rests entirely on architecture and specifications. The RTX 5090 D has measured data across ten tests, all confirming its position in the upper percentile of GPUs. The 50th percentile ranking of the MI455X reflects the absence of test data rather than measured performance, since no benchmark results are recorded for it.

FAQ

Q: Which GPU has more memory bandwidth?

A: The AMD Instinct MI455X has 23.3 TB/s of bandwidth from its HBM4 memory on a 24576-bit bus. The NVIDIA GeForce RTX 5090 D has 1.79 TB/s from GDDR7 on a 512-bit bus.

Q: Can the AMD Instinct MI455X run DirectX or Vulkan applications?

A: No. The database lists DirectX, OpenGL, and Vulkan as N/A for the MI455X. It also has no display outputs, so it cannot drive a monitor or run standard graphics APIs.

Q: What is the average benchmark score for each GPU?

A: The RTX 5090 D has an average benchmark score of 77,712 across ten tests. The MI455X has an average score of 0, with no benchmarks recorded in the database.

Q: How does the RTX 5090 D compare to its nearest rivals?

A: The RTX 5090 D is 1.1 percent above the AMD Radeon RX 6650M XT (76,904), 1.6 percent below the AMD Radeon RX 6850M XT (78,940), 2.1 percent below the NVIDIA Tesla P100 PCIe 12 GB (79,396), and 2.4 percent below the NVIDIA Tesla P100 PCIe 16 GB (79,605).

Q: What is the TDP and power requirement for each card?

A: The MI455X has a TDP of 2300 W and a suggested PSU of 2700 W. The RTX 5090 D has a TDP of 575 W and a suggested PSU of 950 W.

Q: Which GPU has more shading units and texture rate?

A: The MI455X has 32,768 shading units and a texture rate of 2,457.6 GTexel/s. The RTX 5090 D has 21,760 shading units and a texture rate of 1,636.8 GTexel/s.