AMD Instinct MI308X vs NVIDIA GeForce RTX 4090 Max-Q Comparison

FAQ

Q: What are the core architectural identities of these two processors?

A: The AMD Instinct MI308X is built on the CDNA 3.0 architecture using the Aqua Vanjaram chip, while the NVIDIA GeForce RTX 4090 Max-Q uses the Ada Lovelace architecture with the AD103 chip. Both are fabricated on a 5 nm process at TSMC.

Q: How do the memory subsystems compare?

A: The MI308X carries 192 GB of HBM3 memory on an 8192-bit bus with 5.32 TB/s bandwidth. The RTX 4090 Max-Q has 16 GB of GDDR6 on a 256-bit bus with 576.0 GB/s bandwidth. The MI308X offers 12 times the memory capacity and roughly 9.2 times the bandwidth.

Q: Which processor has higher raw compute throughput?

A: The MI308X delivers 81.72 TFLOPS FP32 and FP16 (1:1), whereas the RTX 4090 Max-Q delivers 28.31 TFLOPS in both FP32 and FP16 (1:1). The MI308X provides about 2.9 times the floating-point throughput.

Q: What is the power requirement difference?

A: The MI308X is rated at 750 W TDP with a suggested PSU of 1150 W. The RTX 4090 Max-Q is rated at 80 W TDP and has no suggested PSU listed. The MI308X consumes significantly more power, reflecting its data-center orientation.

Q: Do both support standard graphics APIs?

A: No. The MI308X lists DirectX, OpenGL, and Vulkan as "N/A". The RTX 4090 Max-Q supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The RTX 4090 Max-Q is a fully featured graphics processor, while the MI308X is compute-focused.

Q: What are the physical form factors?

A: The MI308X is an OAM module with no display outputs and no power connectors listed (it relies on the host system). The RTX 4090 Max-Q is an IGP (integrated graphics processor) with display outputs described as "Portable Device Dependent".

Architecture Differences

The AMD Instinct MI308X uses the CDNA 3.0 architecture, a compute-optimized design that omits traditional graphics fixed-function units. The chip, named Aqua Vanjaram, contains 153,000 million transistors on a 1017 mm² die, yielding a transistor density of 150.4M per mm². The architecture includes 19,456 shading units and 1,216 texture mapping units, but has 0 ROPs and no RT cores or tensor cores listed. Pixel rate is recorded as 0 MPixel/s, confirming no rasterization pipeline. Texture rate reaches 2,553.6 GTexel/s. The memory subsystem uses HBM3 with 192 GB capacity and 5.32 TB/s bandwidth across an 8192-bit bus. The FP32 and FP16 throughput are both 81.72 TFLOPS with a 1:1 ratio, indicating no dedicated tensor hardware and a uniform compute rate.

The NVIDIA GeForce RTX 4090 Max-Q is based on Ada Lovelace, a graphics-oriented architecture. The AD103 chip contains 45,900 million transistors on a 379 mm² die, with a transistor density of 121.1M per mm². It has 9,728 shading units, 304 TMUs, 112 ROPs, 76 RT cores, and 304 tensor cores. Pixel rate is 163.0 GPixel/s and texture rate is 442.3 GTexel/s. Memory is 16 GB of GDDR6 on a 256-bit bus, delivering 576.0 GB/s. FP32 and FP16 both measure 28.31 TFLOPS (1:1), with tensor cores providing additional AI-specific throughput not separately listed.

The two architectures diverge in purpose. CDNA 3.0 strips out graphics features entirely, maximizing compute density and memory bandwidth for data-center workloads. Ada Lovelace retains a full graphics pipeline with ray tracing and tensor acceleration, targeting portable gaming and workstation use. The MI308X has no display outputs, while the RTX 4090 Max-Q supports portable device dependent displays. API support reflects this split: the MI308X reports N/A for DirectX, OpenGL, and Vulkan, whereas the RTX 4090 Max-Q supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4.

Head-to-Head Benchmarks

The database records no head-to-head benchmark entries for this pair, so direct measured scores are unavailable. Both processors hold a percentile rank of 50 against all GPUs, with an average benchmark score of 0 in the recorded data. This makes quantitative comparison impossible from benchmark results alone.

However, the recorded specifications permit a comparative analysis of theoretical capabilities. The MI308X's FP32 throughput of 81.72 TFLOPS is approximately 2.9 times the RTX 4090 Max-Q's 28.31 TFLOPS. In texture processing, the MI308X achieves 2,553.6 GTexel/s versus 442.3 GTexel/s, a factor of about 5.8. Memory bandwidth differs even more starkly: 5.32 TB/s against 576.0 GB/s, which is roughly 9.2 times higher for the MI308X.

The RTX 4090 Max-Q counters in graphics-specific metrics. Its pixel rate of 163.0 GPixel/s far exceeds the MI308X's 0 MPixel/s, confirming that the NVIDIA part can render frames while the AMD part cannot. The RTX 4090 Max-Q also has 76 RT cores and 304 tensor cores, features absent from the MI308X's specification list. These hardware units enable ray tracing and AI-accelerated features that the MI308X lacks entirely.

Clock speeds also differ. The MI308X runs at a 1000 MHz base and 2100 MHz boost, while the RTX 4090 Max-Q runs at 930 MHz base and 1455 MHz boost. Despite the lower clocks, the RTX 4090 Max-Q's efficiency advantage is evident from its 80 W TDP versus the MI308X's 750 W TDP. The MI308X uses its massive transistor count and memory bus to achieve higher absolute throughput, while the RTX 4090 Max-Q delivers moderate performance at a fraction of the power draw.

Specification Differences

| Specification | AMD Instinct MI308X | NVIDIA GeForce RTX 4090 Max-Q |

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

| 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 | 930 MHz |

| Boost clock | 2100 MHz | 1455 MHz |

| Memory clock | 1300 MHz, 5.2 Gbps effective | 2250 MHz, 18 Gbps effective |

| 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 | 19,456 | 9,728 |

| TMUs | 1,216 | 304 |

| ROPs | 0 | 112 |

| RT cores | None listed | 76 |

| Tensor cores | None listed | 304 |

| Pixel rate | 0 MPixel/s | 163.0 GPixel/s |

| Texture rate | 2,553.6 GTexel/s | 442.3 GTexel/s |

| FP32 | 81.72 TFLOPS | 28.31 TFLOPS |

| FP16 | 81.72 TFLOPS (1:1) | 28.31 TFLOPS (1:1) |

| TDP | 750 W | 80 W |

| Slot width | OAM Module | IGP |

| Power connectors | None | None |

| Suggested PSU | 1150 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 |

| Production status | Not listed | Active |

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

| Predecessor | Radeon Instinct | GeForce 30 Mobile |

| Successor | Not listed | GeForce 50 Mobile |

The Verdict

The data shows two processors designed for entirely different workloads. The AMD Instinct MI308X is a data-center compute accelerator with no graphics output, no rasterization pipeline, and no graphics API support. Its 192 GB HBM3 memory and 5.32 TB/s bandwidth target large-scale compute tasks like AI training or scientific simulation, where memory capacity and bandwidth dominate. The 750 W TDP and OAM form factor place it in server racks with dedicated power delivery.

The NVIDIA GeForce RTX 4090 Max-Q is a mobile graphics processor with an 80 W TDP and IGP form factor. It supports full DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, includes 76 RT cores and 304 tensor cores, and produces 163.0 GPixel/s. This configuration suits portable devices where rasterization, ray tracing, and power efficiency matter.

Benchmark results are absent from the database, so the verdict relies on architectural evidence. The MI308X wins decisively in raw compute and memory metrics: 2.9 times the FP32 throughput, 5.8 times the texture rate, and 9.2 times the memory bandwidth. The RTX 4090 Max-Q wins in every graphics-specific metric: pixel rate, RT cores, tensor cores, and API compatibility. No single metric places one above the other across all categories because they do not compete in the same market segment.

The release dates differ by roughly eleven months: the RTX 4090 Max-Q launched 2023-01-02, and the MI308X launched 2023-12-05. The RTX 4090 Max-Q remains in active production, while the MI308X has no production status listed. The RTX 4090 Max-Q has a successor, the GeForce 50 Mobile, whereas the MI308X lists none.

Where Each One Wins

AMD Instinct MI308X wins in compute density and memory capacity. The 81.72 TFLOPS FP32 rate more than doubles the RTX 4090 Max-Q's 28.31 TFLOPS. The 192 GB memory pool is 12 times larger than 16 GB, and the 5.32 TB/s bandwidth is over 9 times higher. The 1,216 TMUs and 2,553.6 GTexel/s texture rate dominate, useful for compute workloads that rely on texture sampling. The 8192-bit memory bus and PCIe 5.0 x16 interface position it for high-throughput data movement. The 153,000 million transistors on a 1017 mm² die reflect a design optimized for massive parallel execution.

NVIDIA GeForce RTX 4090 Max-Q wins in graphics and power efficiency. The 112 ROPs and 163.0 GPixel/s pixel rate provide actual display output, which the MI308X cannot deliver. The 76 RT cores and 304 tensor cores enable hardware-accelerated ray tracing and AI features, capabilities entirely absent from the MI308X's specification list. The 80 W TDP is roughly 9.4 percent of the MI308X's 750 W TDP, making it suitable for battery-powered devices. Full support for DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4 ensures broad software compatibility, while the MI308X lists N/A for all three. The 18 Gbps effective memory clock on GDDR6 provides fast access for a 256-bit bus, and the PCIe 4.0 x16 interface matches typical mobile platforms. The RTX 4090 Max-Q also has an active production status and a defined successor, indicating an ongoing product lifecycle.

Use-case split: The MI308X serves high-performance compute clusters where memory capacity and FP32 throughput are paramount. The RTX 4090 Max-Q serves laptops and portable devices that need graphics rendering, ray tracing, AI acceleration, and low power consumption. The two overlap only in the abstract sense of being 5 nm GPUs from rival manufacturers; their design targets do not intersect. The absence of head-to-head benchmarks in the database reflects this separation, as no standard benchmark suite would meaningfully compare a 750 W OAM accelerator with no display outputs against an 80 W mobile IGP with full graphics support.