AMD Instinct MI355X vs NVIDIA RTX 4000 Mobile Ada Generation Comparison

Where Each One Wins

The AMD Instinct MI355X and NVIDIA RTX 4000 Mobile Ada Generation occupy completely different corners of the GPU landscape, and the recorded data shows no direct benchmark overlap between them. The MI355X is an OAM module designed for rack-scale compute, with a 1400 W TDP and no display outputs. The RTX 4000 Mobile is an IGP for laptops, with a 110 W TDP and portable-device-dependent display outputs. The MI355X wins outright on raw compute throughput, memory capacity, and memory bandwidth. The RTX 4000 Mobile wins on power efficiency, feature completeness for graphics APIs, and physical integration into mobile systems.

The MI355X delivers 78.64 TFLOPS FP32 and the same 78.64 TFLOPS FP16 (1:1), which is more than three times the FP32 throughput of the RTX 4000 Mobile at 24.72 TFLOPS. Its memory subsystem is in a different class: 288 GB of HBM3e on an 8192-bit bus with 8.19 TB/s bandwidth, versus 12 GB of GDDR6 on a 192-bit bus with 432.0 GB/s. For AI training, large-model inference, or HPC workloads that saturate memory bandwidth, the MI355X is the clear choice. The RTX 4000 Mobile wins where portability and API support matter: it supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, while the MI355X reports N/A for all three. It also has 58 RT cores and 232 tensor cores, hardware that the MI355X does not list. The data indicates the MI355X is a compute accelerator, while the RTX 4000 Mobile is a full-featured mobile graphics processor.

Architecture Differences

The two chips share a foundry but little else. Both use TSMC, but the MI355X is built on a 3 nm process with 185,000 million transistors on a 2380 mm² die, yielding a transistor density of 77.7M per mm². The RTX 4000 Mobile uses a 5 nm process with 35,800 million transistors on a 294 mm² die, giving a much higher density of 121.8M per mm². The MI355X uses the CDNA 4.0 architecture, part of the Instinct (MIx) generation, while the RTX 4000 Mobile uses Ada Lovelace, part of the GeForce 40-series, with the generation field listed as Ada-MW.

The MI355X chip is labeled MI350 256CU, indicating 256 compute units. That translates to 16,384 shading units, 1,024 texture mapping units, and zero ROPs, with a pixel rate of 0 MPixel/s. The RTX 4000 Mobile uses the AD104 chip with 7,424 shading units, 232 TMUs, 80 ROPs, 58 RT cores, and 232 tensor cores, producing a pixel rate of 133.2 GPixel/s. The MI355X has no RT or tensor core counts listed, no display outputs, and no API support. The RTX 4000 Mobile is a complete graphics processor with ray tracing, tensor acceleration, and full API compatibility.

Memory architecture diverges sharply. The MI355X uses HBM3e with 288 GB capacity, 8192-bit bus width, and 8.19 TB/s bandwidth. The RTX 4000 Mobile uses GDDR6 with 12 GB capacity, 192-bit bus width, and 432.0 GB/s bandwidth. Clock behavior also differs: the MI355X has a base clock of 1000 MHz and boost of 2400 MHz, with memory at 2000 MHz (8 Gbps effective). The RTX 4000 Mobile has a higher base of 1290 MHz but a lower boost of 1665 MHz, with memory at 2250 MHz (18 Gbps effective). The MI355X uses a PCIe 5.0 x16 interface; the RTX 4000 Mobile uses PCIe 4.0 x16. The MI355X is an OAM module with no power connectors and a suggested PSU of 1800 W; the RTX 4000 Mobile is an IGP with no power connectors and no suggested PSU.

FAQ

Q: Which GPU has more memory bandwidth?

A: The AMD Instinct MI355X has 8.19 TB/s of bandwidth from HBM3e on an 8192-bit bus. The NVIDIA RTX 4000 Mobile has 432.0 GB/s from GDDR6 on a 192-bit bus. The MI355X provides roughly 19 times the bandwidth.

Q: Can the AMD Instinct MI355X run DirectX games?

A: No. The MI355X lists DirectX as N/A, along with OpenGL and Vulkan as N/A. It has no display outputs. The RTX 4000 Mobile supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Q: What is the power draw difference?

A: The MI355X has a TDP of 1400 W and a suggested PSU of 1800 W. The RTX 4000 Mobile has a TDP of 110 W and no suggested PSU listed. The MI355X consumes over 12 times the power of the RTX 4000 Mobile.

Q: Which GPU has ray tracing hardware?

A: The RTX 4000 Mobile has 58 RT cores and 232 tensor cores. The MI355X does not list RT core or tensor core counts, and its architecture is CDNA 4.0, which the data records without those features.

Q: How do the FP32 compute figures compare?

A: The MI355X delivers 78.64 TFLOPS FP32. The RTX 4000 Mobile delivers 24.72 TFLOPS FP32. The MI355X is 53.92 TFLOPS higher, which is about 3.2 times the RTX 4000 Mobile's throughput.

Q: What are the physical differences in form factor?

A: The MI355X is an OAM Module measuring 102 mm in length and 165 mm in width. The RTX 4000 Mobile is an IGP with no listed dimensions. The MI355X has no display outputs; the RTX 4000 Mobile's outputs are portable device dependent.

Specification Differences

| Specification | AMD Instinct MI355X | NVIDIA RTX 4000 Mobile Ada Generation |

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

| Architecture | CDNA 4.0 | Ada Lovelace |

| Generation | Instinct (MIx) | Ada-MW |

| Process Node | 3 nm | 5 nm |

| Transistors | 185,000 million | 35,800 million |

| Die Size | 2380 mm² | 294 mm² |

| Transistor Density | 77.7M / mm² | 121.8M / mm² |

| Base Clock | 1000 MHz | 1290 MHz |

| Boost Clock | 2400 MHz | 1665 MHz |

| Memory Clock | 2000 MHz, 8 Gbps effective | 2250 MHz, 18 Gbps effective |

| Memory Size | 288 GB | 12 GB |

| Memory Type | HBM3e | GDDR6 |

| Memory Bus Width | 8192 bit | 192 bit |

| Memory Bandwidth | 8.19 TB/s | 432.0 GB/s |

| Shading Units | 16,384 | 7,424 |

| TMUs | 1,024 | 232 |

| ROPs | 0 | 80 |

| RT Cores | Not listed | 58 |

| Tensor Cores | Not listed | 232 |

| Pixel Rate | 0 MPixel/s | 133.2 GPixel/s |

| Texture Rate | 2,457.6 GTexel/s | 386.3 GTexel/s |

| FP32 | 78.64 TFLOPS | 24.72 TFLOPS |

| FP16 | 78.64 TFLOPS (1:1) | 24.72 TFLOPS (1:1) |

| TDP | 1400 W | 110 W |

| Slot Width | OAM Module | IGP |

| Power Connectors | None | None |

| Suggested PSU | 1800 W | Not listed |

| Bus Interface | PCIe 5.0 x16 | PCIe 4.0 x16 |

| Display Outputs | No outputs | Portable Device Dependent |

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

| OpenGL | N/A | 4.6 |

| Vulkan | N/A | 1.4 |

| Dimensions | 102 mm length, 165 mm width | Not listed |

| Release Date | 2025-06-11 | 2023-03-20 |

| Predecessor | Radeon Instinct | Ampere-MW |

| Successor | Not listed | Blackwell-MW |

| Production Status | Not listed | Active |

Head-to-Head Benchmarks

The database contains no direct head-to-head benchmark results between these two GPUs, and both have an average benchmark score of 0 with a percentile rank of 50 against all GPUs. The comparison must therefore rest on the recorded specification data, which shows decisive wins in opposite directions.

The MI355X dominates raw compute. Its FP32 throughput of 78.64 TFLOPS exceeds the RTX 4000 Mobile's 24.72 TFLOPS by 53.92 TFLOPS, a margin of roughly 3.2 times. Its FP16 throughput is identical to its FP32 at 78.64 TFLOPS, indicating a 1:1 ratio, while the RTX 4000 Mobile also runs FP16 at 1:1 with 24.72 TFLOPS. Texture rate favors the MI355X at 2,457.6 GTexel/s versus 386.3 GTexel/s, a difference of 2,071.3 GTexel/s. The MI355X has 16,384 shading units versus 7,424, and 1,024 TMUs versus 232. The RTX 4000 Mobile counters with 80 ROPs versus 0, giving it a pixel rate of 133.2 GPixel/s against the MI355X's 0 MPixel/s.

Memory is the most lopsided category. The MI355X carries 288 GB of HBM3e, which is 276 GB more than the RTX 4000 Mobile's 12 GB. Its bus width of 8192 bit is 8000 bit wider than the 192-bit bus of the RTX 4000 Mobile. Bandwidth tells the same story: 8.19 TB/s versus 432.0 GB/s. The MI355X provides 7.758 TB/s more bandwidth, approximately 19 times as much. Clock speeds split the difference: the RTX 4000 Mobile has a higher base clock at 1290 MHz versus 1000 MHz, but the MI355X boosts to 2400 MHz versus 1665 MHz. The RTX 4000 Mobile's memory runs at a higher effective speed of 18 Gbps versus 8 Gbps, though the MI355X's far wider bus makes that irrelevant for total bandwidth.

Power and physical requirements separate them completely. The MI355X draws 1400 W TDP and needs a suggested PSU of 1800 W, whereas the RTX 4000 Mobile draws 110 W and lists no PSU requirement. The MI355X is an OAM module with no display outputs and no API support. The RTX 4000 Mobile is an IGP with portable device dependent outputs and full support for DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4. The MI355X released on 2025-06-11, while the RTX 4000 Mobile released on 2023-03-20. The MI355X's predecessor is Radeon Instinct, and the RTX 4000 Mobile's predecessor is Ampere-MW with a successor of Blackwell-MW.

The Verdict

The data points to a straightforward conclusion: these are not competing products, and no single winner exists across all criteria. The AMD Instinct MI355X is a data-center compute accelerator. Its 78.64 TFLOPS FP32, 288 GB HBM3e, 8.19 TB/s bandwidth, and 8192-bit bus make it suitable for memory-bound and compute-bound workloads such as large model inference or HPC simulation. Its 1400 W TDP and 1800 W suggested PSU confirm it belongs in a server chassis, not a desktop or laptop. Its lack of display outputs and N/A API support mean it cannot function as a graphics card.

The NVIDIA RTX 4000 Mobile Ada Generation is a mobile graphics processor. Its 110 W TDP, IGP form factor, and portable device dependent display outputs place it inside laptops. Its 58 RT cores, 232 tensor cores, and support for DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4 make it a complete graphics solution for gaming, content creation, and CUDA-accelerated workflows. Its 24.72 TFLOPS FP32 is modest compared to the MI355X, but its 133.2 GPixel/s pixel rate and 80 ROPs are features the MI355X simply does not have.

A buyer needing maximum compute density and memory capacity should select the MI355X, provided the 1400 W power envelope and OAM slot are acceptable. A buyer needing a mobile GPU with ray tracing, tensor cores, and full graphics API support should select the RTX 4000 Mobile. The benchmark database records no overlap in their intended use cases, and the specification data confirms that each device wins where it is designed to operate.