AMD Instinct MI355X vs NVIDIA GeForce RTX 4090 D Comparison

AMD Instinct MI355X and NVIDIA GeForce RTX 4090 D occupy different tiers of the GPU market, targeting distinct workloads with radically different design philosophies. The database records the MI355X as a compute-oriented accelerator with a 50th percentile ranking across all GPUs, while the RTX 4090 D sits at the 98th percentile, indicating its dominance in consumer-grade benchmark suites. However, the MI355X’s raw specifications, particularly memory capacity and bandwidth, position it for data center tasks that the RTX 4090 D cannot accommodate. The recorded data shows a clear split: the RTX 4090 D wins on software ecosystem and rasterization features, while the MI355X leads in sheer memory scale and interface width. This analysis walks through the benchmark results, architecture differences, and specification gaps to clarify where each product stands.

Where Each One Wins

The RTX 4090 D holds all recorded benchmark wins in the database. In 3DMark Steel Nomad DX12, it scores 8,587 points, a figure that reflects its gaming-oriented geometry and pixel processing strengths. Its Geekbench OpenCL score of 278,621 and Vulkan score of 246,941 further confirm its lead in general-purpose compute workloads that rely on driver maturity and API support. The MI355X has no recorded benchmark scores, so the data shows zero wins for the AMD part. This absence does not indicate inferiority in all tasks; rather, it reflects that the MI355X targets server environments where standard consumer benchmarks are rarely run. The RTX 4090 D’s wins are thus limited to the tests available in the database, which favor its feature set. The MI355X’s potential wins would appear in memory-bound or multi-GPU scaling scenarios, but the database lacks such measurements. Therefore, the recorded data indicates the RTX 4090 D wins everywhere it is tested, while the MI355X wins on paper in memory capacity and bus width, with no empirical score to validate that advantage.

Architecture Differences

The two GPUs diverge fundamentally at the architecture level. The MI355X uses CDNA 4.0, AMD’s compute-focused design, built on a 3 nm TSMC process with 185,000 million transistors on a 2,380 mm² die. This yields a transistor density of 77.7M per mm². The RTX 4090 D uses Ada Lovelace, NVIDIA’s consumer architecture, on a 5 nm TSMC process with 76,300 million transistors on a 609 mm² die, achieving 125.3M transistors per mm². The MI355X’s die is nearly four times larger, prioritizing raw compute and memory integration over efficiency. The RTX 4090 D integrates 114 RT cores and 456 tensor cores, enabling hardware-accelerated ray tracing and AI inference. The MI355X lists no RT or tensor core counts, aligning with CDNA’s focus on FP32/FP16 throughput rather than graphics-specific features. The MI355X also reports zero ROPs and a pixel rate of 0 MPixel/s, confirming it has no display output capability. The RTX 4090 D has 176 ROPs and a pixel rate of 443.5 GPixel/s, along with display outputs (1x HDMI 2.1, 3x DisplayPort 1.4a). Memory architecture differs starkly: the MI355X uses HBM3e across an 8,192-bit bus, while the RTX 4090 D uses GDDR6X across a 384-bit bus. The MI355X’s 8.19 TB/s bandwidth is 8.1 times the RTX 4090 D’s 1.01 TB/s. Clock behavior also varies: the MI355X runs at 1,000 MHz base and 2,400 MHz boost, while the RTX 4090 D starts at 2,280 MHz and boosts to 2,520 MHz. The MI355X’s lower clocks reflect its HBM and compute-optimized design, trading frequency for massive parallel throughput.

FAQ

Q: Why does the MI355X have no benchmark scores in the database?

A: The recorded data lists benchmarks only for the RTX 4090 D. The MI355X’s benchmark array is empty, and its average score is 0, placing it at the 50th percentile. This likely occurs because the MI355X targets server deployments where standard consumer benchmarks are not applied.

Q: Which GPU has higher memory bandwidth?

A: The MI355X leads decisively with 8.19 TB/s from HBM3e memory on an 8,192-bit bus. The RTX 4090 D delivers 1.01 TB/s via GDDR6X on a 384-bit bus. The MI355X’s bandwidth is roughly 8.1 times higher.

Q: Does the RTX 4090 D support ray tracing?

A: Yes, the RTX 4090 D includes 114 RT cores and supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4. The MI355X lists N/A for DirectX, OpenGL, and Vulkan, indicating no graphics API support.

Q: What is the power consumption difference?

A: The MI355X has a TDP of 1,400 W with a suggested PSU of 1,800 W. The RTX 4090 D has a TDP of 425 W with a suggested PSU of 800 W. The MI355X requires 3.3 times the power budget.

Q: Can the MI355X output video to a display?

A: No, the MI355X has no display outputs and a pixel rate of 0 MPixel/s. The RTX 4090 D includes 1x HDMI 2.1 and 3x DisplayPort 1.4a, making it a complete graphics solution.

Q: Which GPU has more shading units?

A: The MI355X has 16,384 shading units versus 14,592 on the RTX 4090 D. However, the RTX 4090 D’s higher boost clock (2,520 MHz vs 2,400 MHz) narrows the FP32 gap: 78.64 TFLOPS for the MI355X versus 73.54 TFLOPS for the RTX 4090 D.

Specification Differences

The specification table shows only the fields where the two GPUs differ. Process node: 3 nm (MI355X) versus 5 nm (RTX 4090 D). Transistor count: 185,000 million versus 76,300 million. Die size: 2,380 mm² versus 609 mm². Transistor density: 77.7M/mm² versus 125.3M/mm². Base clock: 1,000 MHz versus 2,280 MHz. Boost clock: 2,400 MHz versus 2,520 MHz. Memory clock: 2,000 MHz (8 Gbps effective) versus 1,313 MHz (21 Gbps effective). Memory size: 288 GB versus 24 GB. Memory type: HBM3e versus GDDR6X. Bus width: 8,192 bit versus 384 bit. Bandwidth: 8.19 TB/s versus 1.01 TB/s. Shading units: 16,384 versus 14,592. TMUs: 1,024 versus 456. ROPs: 0 versus 176. RT cores: null versus 114. Tensor cores: null versus 456. Pixel rate: 0 MPixel/s versus 443.5 GPixel/s. Texture rate: 2,457.6 GTexel/s versus 1,149.1 GTexel/s. FP32: 78.64 TFLOPS versus 73.54 TFLOPS. FP16: identical at 78.64 TFLOPS versus 73.54 TFLOPS. TDP: 1,400 W versus 425 W. Slot width: OAM Module versus Triple-slot. Power connectors: None versus 1x 16-pin. Suggested PSU: 1,800 W versus 800 W. Bus interface: PCIe 5.0 x16 versus PCIe 4.0 x16. Display outputs: No outputs versus 1x HDMI 2.1, 3x DisplayPort 1.4a. APIs: N/A versus DirectX 12 Ultimate, OpenGL 4.6, Vulkan 1.4. Dimensions: 102 mm length, 165 mm width versus 304 mm length, 137 mm height, 61 mm width. Release date: 2025-06-11 versus 2023-12-27. Production status: null versus End-of-life. Successor: null versus GeForce 50. Predecessor: Radeon Instinct versus GeForce 30. Launch MSRP: null versus 1,599 USD.

Head-to-Head Benchmarks

The database contains no direct head-to-head benchmark comparisons between the MI355X and RTX 4090 D. The wins count is 0 for both, indicating no shared tests. The RTX 4090 D’s standalone scores provide the only numerical anchor. In 3DMark Steel Nomad DX12, it scores 8,587 points, a measure of its rasterization and compute throughput under directX 12. This test would be meaningless for the MI355X, which lacks DirectX support. The Geekbench OpenCL score of 278,621 and Vulkan score of 246,941 show the RTX 4090 D’s cross-platform compute strength. The MI355X’s FP32 output of 78.64 TFLOPS exceeds the RTX 4090 D’s 73.54 TFLOPS by 6.9%, but this theoretical advantage lacks empirical validation in the database. Texture rate favors the MI355X at 2,457.6 GTexel/s versus 1,149.1 GTexel/s, a 2.1 times lead. Pixel rate reverses the order: the RTX 4090 D produces 443.5 GPixel/s versus 0 for the MI355X. The nearest rivals for the RTX 4090 D provide context for its benchmark standing: it trails the NVIDIA RTX PRO 5000 Blackwell by 2.2%, the A100 SXM4 80 GB by 3.1%, the RTX 5000 Ada Generation by 3.6%, and the A100 SXM4 40 GB by 4.9%. These deltas confirm the RTX 4090 D sits at the top of consumer GPU performance, while the MI355X’s lack of scores leaves its competitive position undefined.

The Verdict

The data directs different buyers to each GPU. The RTX 4090 D is the choice for anyone needing graphics output, ray tracing, and broad software support. Its 98th percentile ranking, 114 RT cores, 456 tensor cores, and display outputs make it a complete consumer or workstation card. The MI355X is for compute environments that prioritize memory capacity and bandwidth above all else. Its 288 GB of HBM3e and 8.19 TB/s bandwidth dwarf the RTX 4090 D’s 24 GB and 1.01 TB/s, making it suitable for large model inference or scientific simulation. The MI355X’s lack of display outputs and graphics APIs confirms it is not a desktop GPU. Power and physical form also separate them: the MI355X consumes 1,400 W and mounts as an OAM module, while the RTX 4090 D draws 425 W and fits a triple-slot PCIe card. The RTX 4090 D’s launch MSRP of 1,599 USD reflects its consumer positioning, while the MI355X has no recorded price. Benchmark results favor the RTX 4090 D in all recorded tests, but those tests do not exercise the MI355X’s unique strengths. The verdict is straightforward: choose the RTX 4090 D for graphics and general compute, choose the MI355X for memory-bound data center workloads. The database shows no overlap in their intended use cases, and the specification gap reinforces that divide.