AMD Instinct MI308X vs NVIDIA GeForce RTX 4090 Mobile Comparison

Where Each One Wins

The two accelerators occupy completely different segments, which is immediately visible in the recorded data. The AMD Instinct MI308X is a data center compute module with no display outputs, no DirectX support, and no benchmark entries in the database. Its percentile rank against all GPUs sits at 50, with an average benchmark score of zero. The NVIDIA GeForce RTX 4090 Mobile, by contrast, is an integrated graphics processor for portable devices, delivering a full suite of DirectX, OpenGL, and Vulkan APIs, and it holds an 84th percentile ranking against all GPUs with an average benchmark score of 43,667.

The use-case split is therefore stark. The MI308X wins in raw compute capacity: it carries 19,456 shading units versus 9,728 on the RTX 4090 Mobile, and its FP32 throughput of 81.72 TFLOPS more than doubles the NVIDIA part's 32.98 TFLOPS. Texture rate also favors AMD heavily, at 2,553.6 GTexel/s versus 515.3 GTexel/s. For workloads that need massive memory capacity, the MI308X provides 192 GB of HBM3 across an 8192-bit bus, delivering 5.32 TB/s of bandwidth. The RTX 4090 Mobile offers 16 GB of GDDR6 on a 256-bit bus at 576.0 GB/s.

The RTX 4090 Mobile wins in every measured benchmark category available in the database. Its Geekbench OpenCL score is 180,831, its Vulkan score is 170,774, and its Passmark G3D score is 27,212. The MI308X has no recorded benchmarks, so the database shows zero wins for AMD and zero wins for NVIDIA in head-to-head tests; all of the NVIDIA scores stand alone. The NVIDIA part also has pixel rendering capability at 189.8 GPixel/s, while the MI308X is listed at 0 MPixel/s, confirming the AMD part has no raster output stages (112 ROPs on NVIDIA, 0 on AMD).

Architecture Differences

The two chips come from entirely different architectural lineages. The MI308X uses the CDNA 3.0 architecture on the Aqua Vanjaram chip, built for compute acceleration in server environments. The RTX 4090 Mobile uses Ada Lovelace on the AD103 chip, designed for graphics rendering and gaming in portable devices. Both are fabricated on a 5 nm process at TSMC, but the die sizes diverge enormously: the MI308X measures 1017 mm² with 153,000 million transistors, while the AD103 is 379 mm² with 45,900 million transistors. Transistor density also differs, with AMD at 150.4 million per mm² and NVIDIA at 121.1 million per mm².

Clock behavior reflects the different design goals. The MI308X has a base clock of 1000 MHz and a boost clock of 2100 MHz, while the RTX 4090 Mobile runs at 1335 MHz base and 1695 MHz boost. The AMD part has a higher peak clock, but the NVIDIA part starts from a higher baseline. Memory clocks differ as well: the MI308X uses 1300 MHz with 5.2 Gbps effective data rate, while the RTX 4090 Mobile runs at 2250 MHz with 18 Gbps effective.

Feature sets are nearly opposite. The MI308X has no RT cores, no tensor cores, no ROPs, and no display outputs. The RTX 4090 Mobile has 76 RT cores, 304 tensor cores, 112 ROPs, and portable-device-dependent display outputs. API support tells the same story: AMD lists N/A for DirectX, OpenGL, and Vulkan, while NVIDIA supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The bus interface also differs, with PCIe 5.0 x16 on the AMD side and PCIe 4.0 x16 on the NVIDIA side.

Power characteristics are not directly comparable because the MI308X consumes 750 W as an OAM module with no power connectors, while the RTX 4090 Mobile is an IGP rated at 120 W. The AMD part suggests a 1150 W power supply, while the NVIDIA part lists no suggested PSU. Release dates place the MI308X at December 2023, and the RTX 4090 Mobile at January 2023, making NVIDIA the earlier release. The MI308X predecessor is Radeon Instinct, the RTX 4090 Mobile predecessor is GeForce 30 Mobile, and the RTX 4090 Mobile successor is GeForce 50 Mobile; the AMD part has no successor listed.

Head-to-Head Benchmarks

The database contains no direct head-to-head benchmark entries between these two parts, so the comparison relies on the recorded scores for the RTX 4090 Mobile and the absence of any scores for the MI308X. The MI308X has zero benchmark results, which means its average benchmark score is zero and its percentile rank is 50. The RTX 4090 Mobile has nine benchmark entries, ranging from a Passmark DirectX 9 score of 310 down to a Passmark DirectX 12 score of 107.

The largest single score for the NVIDIA part is the Geekbench OpenCL result of 180,831, followed by the Geekbench Vulkan result of 170,774. These two tests measure compute throughput under OpenCL and Vulkan APIs, and they show the RTX 4090 Mobile delivering substantial compute performance despite its mobile form factor. The Passmark G3D score of 27,212 is the graphics-oriented result, while the Passmark GPU Compute score of 12,347 measures compute workloads separately from graphics. The 2D graphics score of 984 is lower, reflecting the limited 2D workload relevance.

The MI308X has no comparable scores, so no delta percentages can be calculated between the two parts. The nearest rivals for the RTX 4090 Mobile are all NVIDIA products: the Quadro M6000 with an average score of 43,301 and a delta of 0.8%, the GeForce RTX 5050 Mobile at 43,268 with a delta of 0.9%, the Quadro M6000 24 GB at 43,262 with a delta of 0.9%, and the RTX A6000 at 44,075 with a delta of -0.9%. These deltas place the RTX 4090 Mobile essentially in a tight cluster with those four cards, all within one percent of each other. The MI308X has no nearest rivals listed.

The Verdict

The data supports a clear separation of purpose. The AMD Instinct MI308X is a compute accelerator for server workloads that require massive memory capacity and raw FP32 throughput, but it cannot render graphics, has no display outputs, and has no benchmark scores in the database. Its 192 GB of HBM3 memory and 5.32 TB/s bandwidth make it suitable for large model training or inference workloads where memory capacity dominates. The 750 W power draw and OAM module form factor confirm a data center installation profile.

The NVIDIA GeForce RTX 4090 Mobile is a portable graphics processor with full API support and a complete set of rendering features, including 76 RT cores and 304 tensor cores. Its benchmark scores are all recorded and strong, with an 84th percentile rank against all GPUs. The 16 GB GDDR6 memory and 576.0 GB/s bandwidth are modest by comparison, but the part operates at 120 W, which suits mobile chassis constraints. The PCIe 4.0 x16 interface is also more typical of mobile implementations.

Given the recorded data, the MI308X should be chosen for compute-only environments where memory capacity and FP32 throughput are the primary requirements, and where no graphics output is needed. The RTX 4090 Mobile should be chosen for portable systems that need both graphics rendering and compute capability, with the advantage of lower power consumption and a full software stack. The MI308X has no benchmark presence, so its performance cannot be quantified from database measurements; the RTX 4090 Mobile has a complete benchmark profile that validates its positioning.

FAQ

Q: What is the memory capacity difference between the two parts?

A: The AMD Instinct MI308X has 192 GB of HBM3 memory, while the NVIDIA GeForce RTX 4090 Mobile has 16 GB of GDDR6 memory.

Q: Which part has higher FP32 compute throughput?

A: The MI308X delivers 81.72 TFLOPS of FP32, compared to 32.98 TFLOPS for the RTX 4090 Mobile.

Q: Does the MI308X support graphics APIs?

A: No, the MI308X lists N/A for DirectX, OpenGL, and Vulkan, and it has no display outputs. The RTX 4090 Mobile supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Q: What are the recorded benchmark scores for the RTX 4090 Mobile?

A: The RTX 4090 Mobile scores 180,831 in Geekbench OpenCL, 170,774 in Geekbench Vulkan, 27,212 in Passmark G3D, 12,347 in Passmark GPU Compute, 984 in Passmark G2D, 310 in Passmark DirectX 9, 262 in Passmark DirectX 11, 173 in Passmark DirectX 10, and 107 in Passmark DirectX 12.

Q: What is the power draw of each part?

A: The MI308X has a TDP of 750 W, while the RTX 4090 Mobile has a TDP of 120 W.

Q: Which part has ray tracing cores?

A: The RTX 4090 Mobile has 76 RT cores and 304 tensor cores. The MI308X has no RT cores and no tensor cores.

Specification Differences

| Specification | AMD Instinct MI308X | NVIDIA GeForce RTX 4090 Mobile |

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

| Architecture | CDNA 3.0 | Ada Lovelace |

| Chip | Aqua Vanjaram | AD103 |

| Process node | 5 nm | 5 nm |

| Transistors | 153,000 million | 45,900 million |

| Die size | 1017 mm² | 379 mm² |

| Transistor density | 150.4M / mm² | 121.1M / mm² |

| Base clock | 1000 MHz | 1335 MHz |

| Boost clock | 2100 MHz | 1695 MHz |

| Memory size | 192 GB | 16 GB |

| Memory type | HBM3 | GDDR6 |

| Memory bus width | 8192 bit | 256 bit |

| Memory bandwidth | 5.32 TB/s | 576.0 GB/s |

| Shading units | 19456 | 9728 |

| TMUs | 1216 | 304 |

| ROPs | 0 | 112 |

| RT cores | None | 76 |

| Tensor cores | None | 304 |

| Pixel rate | 0 MPixel/s | 189.8 GPixel/s |

| Texture rate | 2,553.6 GTexel/s | 515.3 GTexel/s |

| FP32 | 81.72 TFLOPS | 32.98 TFLOPS |

| FP16 | 81.72 TFLOPS (1:1) | 32.98 TFLOPS (1:1) |

| TDP | 750 W | 120 W |

| Slot width | OAM Module | IGP |

| Power connectors | None | None |

| Suggested PSU | 1150 W | None |

| 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 |

| Release date | 2023-12-05 | 2023-01-02 |

| Predecessor | Radeon Instinct | GeForce 30 Mobile |

| Successor | None | GeForce 50 Mobile |

| Production status | Not listed | Active |