AMD Instinct MI300X vs AMD Radeon RX 7900 GRE Comparison

The Verdict

The data presents two AMD accelerators with completely different design objectives. The AMD Instinct MI300X is a compute-focused accelerator with a 317994 Geekbench OpenCL score, placing it in the 100th percentile of all GPUs in the database. The AMD Radeon RX 7900 GRE is a graphics card with a 175758 Geekbench OpenCL score and a 77th percentile ranking. In the single head-to-head benchmark available, the MI300X leads by 80.9%, a decisive margin. The MI300X is the choice for compute workloads where raw OpenCL throughput dominates. The RX 7900 GRE, with a 16 GB frame buffer, 80 ray tracing cores, and a 359.2 GPixel/s pixel rate, serves graphics rendering and rasterization tasks. Its DirectX 12 Ultimate and Vulkan 1.4 API support confirms a consumer graphics orientation. The MI300X has no display outputs and no DirectX, OpenGL, or Vulkan support, making it unsuitable for interactive graphics. Users requiring a display-capable card with modern graphics APIs should choose the RX 7900 GRE. Users prioritizing maximum compute throughput in OpenCL should choose the MI300X.

Architecture Differences

The MI300X uses the Aqua Vanjaram chip built on CDNA 3.0 architecture, while the RX 7900 GRE uses the Navi 31 chip on RDNA 3.0 architecture. Both are fabricated on a 5 nm process at TSMC, but the transistor counts diverge sharply. The MI300X packs 153,000 million transistors on a 1017 mm² die, yielding a transistor density of 150.4 million per mm². The RX 7900 GRE contains 57,700 million transistors on a 529 mm² die, with a density of 109.1 million per mm². The MI300X die is nearly twice the physical size and carries nearly three times the transistor count.

The MI300X uses HBM3 memory totaling 192 GB across an 8192-bit bus, delivering 5.32 TB/s of bandwidth. The RX 7900 GRE uses 16 GB of GDDR6 memory on a 256-bit bus, providing 576.0 GB/s of bandwidth. The memory bandwidth difference is substantial, with the MI300X offering over nine times the bandwidth of the RX 7900 GRE. Shading unit counts also differ: the MI300X has 19,456 shading units and 1,216 texture mapping units, while the RX 7900 GRE has 5,120 shading units, 320 TMUs, and 160 ROPs. The MI300X reports zero ROPs and a 0 MPixel/s pixel rate, confirming it is not designed for rasterization output. The RX 7900 GRE has a 359.2 GPixel/s pixel rate and a 718.4 GTexel/s texture rate. The MI300X texture rate reaches 2,553.6 GTexel/s. The MI300X has no ray tracing cores listed, while the RX 7900 GRE includes 80 of them. Clock behavior differs: the MI300X runs at a 1000 MHz base and 2100 MHz boost, while the RX 7900 GRE runs at 1287 MHz base, 1880 MHz game clock, and 2245 MHz boost. The MI300X memory operates at 1300 MHz with 5.2 Gbps effective, the RX 7900 GRE memory at 2250 MHz with 18 Gbps effective.

The MI300X uses a PCIe 5.0 x16 interface and an OAM Module slot width with no power connectors, requiring a 1150 W suggested PSU. The RX 7900 GRE uses PCIe 4.0 x16, a dual-slot design, two 8-pin power connectors, and a 600 W suggested PSU. The MI300X has no display outputs, while the RX 7900 GRE provides 1x HDMI 2.1a, 2x DisplayPort 2.1, and 1x USB Type-C. API support separates them completely: the MI300X has N/A for DirectX, OpenGL, and Vulkan, whereas the RX 7900 GRE supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The RX 7900 GRE has a successor in Navi IV, while the MI300X lists none. The RX 7900 GRE measures 276 mm in length, 110 mm in height, and 51 mm in width.

FAQ

Q: Which card has higher raw OpenCL compute performance?

A: The AMD Instinct MI300X scores 317994 in Geekbench OpenCL, while the AMD Radeon RX 7900 GRE scores 175758. The MI300X leads by 80.9% in this test.

Q: Can the MI300X output video to a display?

A: No, the MI300X has no display outputs. The RX 7900 GRE includes 1x HDMI 2.1a, 2x DisplayPort 2.1, and 1x USB Type-C outputs.

Q: Which card supports modern graphics APIs?

A: The RX 7900 GRE supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The MI300X lists N/A for DirectX, OpenGL, and Vulkan support.

Q: How do the memory configurations compare?

A: The MI300X has 192 GB of HBM3 memory on an 8192-bit bus with 5.32 TB/s bandwidth. The RX 7900 GRE has 16 GB of GDDR6 memory on a 256-bit bus with 576.0 GB/s bandwidth.

Q: What is the power requirement difference?

A: The MI300X has a 750 W TDP and a suggested PSU of 1150 W. The RX 7900 GRE has a 260 W TDP and a suggested PSU of 600 W.

Q: Which card has ray tracing capabilities?

A: The RX 7900 GRE includes 80 ray tracing cores. The MI300X lists no ray tracing cores in the database.

Specification Differences

| Specification | AMD Instinct MI300X | AMD Radeon RX 7900 GRE |

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

| Chip | Aqua Vanjaram | Navi 31 |

| Architecture | CDNA 3.0 | RDNA 3.0 |

| Generation | Instinct (MIx) | Navi III (RX 7000) |

| Transistors | 153,000 million | 57,700 million |

| Die Size | 1017 mm² | 529 mm² |

| Transistor Density | 150.4M / mm² | 109.1M / mm² |

| Base Clock | 1000 MHz | 1287 MHz |

| Boost Clock | 2100 MHz | 2245 MHz |

| Game Clock | None | 1880 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 | 19456 | 5120 |

| TMUs | 1216 | 320 |

| ROPs | 0 | 160 |

| RT Cores | None | 80 |

| Pixel Rate | 0 MPixel/s | 359.2 GPixel/s |

| Texture Rate | 2,553.6 GTexel/s | 718.4 GTexel/s |

| FP32 | 81.72 TFLOPS | 45.98 TFLOPS |

| FP16 | 81.72 TFLOPS (1:1) | 91.96 TFLOPS (2:1) |

| TDP | 750 W | 260 W |

| Slot Width | OAM Module | Dual-slot |

| Power Connectors | None | 2x 8-pin |

| Suggested PSU | 1150 W | 600 W |

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

| Display Outputs | No outputs | 1x HDMI 2.1a, 2x DisplayPort 2.1, 1x USB Type-C |

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

| OpenGL | N/A | 4.6 |

| Vulkan | N/A | 1.4 |

| Dimensions | Not listed | 276 mm x 110 mm x 51 mm |

| Release Date | 2023-12-05 | 2023-07-26 |

| Predecessor | Radeon Instinct | Navi II |

| Successor | None | Navi IV |

| Launch MSRP | None | 549 USD |

Head-to-Head Benchmarks

The only direct comparison in the database is the Geekbench OpenCL test. The MI300X scores 317994, and the RX 7900 GRE scores 175758. The delta is 80.9% in favor of the MI300X. This is a large margin, reflecting the architectural gulf between a compute accelerator and a consumer graphics card. The MI300X has 19,456 shading units versus 5,120 on the RX 7900 GRE, a 3.8x difference in raw shader hardware. The MI300X memory bandwidth of 5.32 TB/s dwarfs the 576.0 GB/s of the RX 7900 GRE by a factor of 9.2. These hardware differences explain the OpenCL result.

The MI300X sits at the 100th percentile in the database, meaning no other recorded GPU scores higher on average. Its nearest rivals include the NVIDIA B200 at 345482 (MI300X is 8% behind), the NVIDIA H200 NVL at 334891 (MI300X is 5% behind), the NVIDIA L40S at 295763 (MI300X is 7.5% ahead), and the NVIDIA RTX 6000 Ada Generation at 287237 (MI300X is 10.7% ahead). The RX 7900 GRE, at the 77th percentile, sits much lower. Its nearest rivals are clustered tightly around it: the AMD FirePro S10000 at 32388 (RX 7900 GRE is 0.2% ahead), the AMD FirePro S9300 X2 at 32540 (RX 7900 GRE is 0.3% behind), the AMD Radeon RX 590 GME at 32601 (RX 7900 GRE is 0.4% behind), and the AMD Radeon Pro 570X at 32176 (RX 7900 GRE is 0.9% ahead). These rivals are all within 1% of the RX 7900 GRE average score of 32456, indicating a crowded performance tier.

The MI300X average benchmark score is 317994, exactly matching its single OpenCL result. The RX 7900 GRE average benchmark score is 32456, an aggregate of its ten recorded tests. The RX 7900 GRE shows strong results in specific tests: a 27089 Passmark G3D score, a 15016 Passmark GPU Compute score, and a 4814 3DMark Steel Nomad DX12 score. In Passmark DirectX tests, it scores 310 for DirectX 9, 300 for DirectX 11, 139 for DirectX 10, and 107 for DirectX 12. Its Passmark G2D score is 1180. Geekbench Vulkan yields 99850. These varied scores demonstrate graphics capability across multiple APIs, which the MI300X cannot match given its lack of graphics API support.

Where Each One Wins

The MI300X wins decisively in compute throughput. Its Geekbench OpenCL score of 317994 is 80.9% higher than the RX 7900 GRE. Its FP32 output of 81.72 TFLOPS nearly doubles the 45.98 TFLOPS of the RX 7900 GRE. Its FP16 performance is 81.72 TFLOPS at a 1:1 ratio, while the RX 7900 GRE achieves 91.96 TFLOPS at a 2:1 ratio. The MI300X texture rate of 2,553.6 GTexel/s is 3.6x the 718.4 GTexel/s of the RX 7900 GRE. Memory capacity favors the MI300X at 192 GB versus 16 GB, a 12x difference. Bandwidth favors the MI300X at 5.32 TB/s versus 576.0 GB/s. The MI300X also uses the newer PCIe 5.0 x16 interface versus PCIe 4.0 x16 on the RX 7900 GRE. The MI300X has a 750 W TDP versus 260 W, indicating its power draw scales with its compute output.

The RX 7900 GRE wins in graphics-specific features. It has 160 ROPs and an 80-core ray tracing block, enabling rasterization and ray-traced rendering. Its pixel rate of 359.2 GPixel/s is a real output capability, whereas the MI300X reports 0 MPixel/s. The RX 7900 GRE supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, while the MI300X supports none of these. Display outputs exist on the RX 7900 GRE with HDMI 2.1a, DisplayPort 2.1, and USB Type-C, allowing direct monitor connection. The RX 7900 GRE has a game clock of 1880 MHz, a feature absent from the MI300X. It also has a higher boost clock at 2245 MHz versus 2100 MHz. The RX 7900 GRE is a dual-slot card with 2x 8-pin power connectors, fitting standard desktop configurations. Its 16 GB GDDR6 memory, while smaller, is paired with a 256-bit bus and operates at 18 Gbps effective, suitable for graphics workloads. The RX 7900 GRE is currently active in production, while the MI300X production status is not listed. The RX 7900 GRE has a successor in Navi IV, indicating an ongoing product line.

Use-case separation is clear from the data. The MI300X serves compute-heavy environments where OpenCL performance, massive memory capacity, and high bandwidth matter. Its lack of display outputs and graphics APIs means it operates as an accelerator in server or data-center contexts. The RX 7900 GRE serves interactive graphics, ray tracing, and API-compatible rendering. Its display outputs and graphics API support make it a functional consumer card. The 80.9% OpenCL gap confirms that the MI300X is in a different performance class for compute, while the RX 7900 GRE holds the only viable position for graphics output. In the database, the MI300X stands at the 100th percentile among all GPUs, while the RX 7900 GRE sits at the 77th percentile. Each card wins in its designated domain, and the specification differences reinforce that separation.