AMD Instinct MI308X vs AMD Radeon RX 7900 GRE Comparison

Where Each One Wins

The AMD Instinct MI308X and the AMD Radeon RX 7900 GRE serve entirely different purposes, and the recorded data reflects that split clearly. The Instinct MI308X is a compute-oriented accelerator with no display outputs, while the RX 7900 GRE is a conventional graphics card with full display connectivity. The benchmark database contains no recorded scores for the MI308X, leaving its average benchmark score at zero and its percentile versus all GPUs at 50. The RX 7900 GRE, by contrast, has ten recorded benchmark entries across DirectX 10, 11, 12, and 9, OpenCL, Vulkan, G2D, G3D, and compute workloads, with an average benchmark score of 32,456 and a percentile versus all GPUs of 77.

The RX 7900 GRE wins in any scenario that requires rendering, rasterization, or API-level graphics support. Its API coverage includes DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, whereas the MI308X lists N/A for DirectX, OpenGL, and Vulkan. The RX 7900 GRE also delivers 359.2 GPixel/s pixel rate and 718.4 GTexel/s texture rate, while the MI308X reports 0 MPixel/s pixel rate and 2,553.6 GTexel/s texture rate. The texture rate advantage for the MI308X is real, but with no pixel output and no graphics API support, that throughput cannot be channeled into conventional rendering workloads.

The MI308X wins in raw compute throughput and memory capacity. Its FP32 performance is 81.72 TFLOPS versus 45.98 TFLOPS for the RX 7900 GRE. Its memory capacity is 192 GB of HBM3 on an 8192-bit bus, delivering 5.32 TB/s bandwidth, compared to 16 GB of GDDR6 on a 256-bit bus at 576.0 GB/s. The MI308X also uses a PCIe 5.0 x16 interface versus PCIe 4.0 x16 on the RX 7900 GRE. These differences point to a clear separation: the MI308X is built for memory-bound and throughput-bound compute, while the RX 7900 GRE is built for client graphics and general-purpose GPU workloads with display output.

Architecture Differences

Both chips are manufactured by TSMC on a 5 nm process, but they diverge sharply in every other architectural respect. The MI308X uses the CDNA 3.0 architecture with the Aqua Vanjaram chip, while the RX 7900 GRE uses RDNA 3.0 with the Navi 31 chip, codenamed Plum Bonito. CDNA is AMD's compute-focused architecture line, while RDNA is the graphics-focused line. The MI308X belongs to the Instinct (MIx) generation, and the RX 7900 GRE belongs to the Radeon RX 7000 series, generation Navi III.

Transistor counts and die sizes reflect the different design goals. The MI308X packs 153,000 million transistors on a 1017 mm² die, yielding a transistor density of 150.4M per mm². The RX 7900 GRE has 57,700 million transistors on a 529 mm² die, for a density of 109.1M per mm². The MI308X die is nearly twice the size and carries nearly three times the transistor count. Its shading unit count is 19,456 versus 5,120 for the RX 7900 GRE, and its texture mapping units number 1,216 versus 320. The RX 7900 GRE has 160 ROPs and 80 ray tracing cores, while the MI308X reports 0 ROPs and no listed ray tracing cores or tensor cores.

Memory architecture is another fundamental split. The MI308X uses 192 GB of HBM3 across an 8192-bit bus, while the RX 7900 GRE uses 16 GB of GDDR6 across a 256-bit bus. The MI308X memory clock is listed at 1300 MHz with 5.2 Gbps effective, and the RX 7900 GRE memory clock is 2250 MHz with 18 Gbps effective. Bandwidth heavily favors the MI308X at 5.32 TB/s versus 576.0 GB/s. Clock speeds are closer than the throughput numbers suggest: the MI308X base clock is 1000 MHz with a 2100 MHz boost, while the RX 7900 GRE base clock is 1287 MHz, game clock 1880 MHz, and boost clock 2245 MHz.

FP16 throughput reveals another architectural difference. The MI308X delivers 81.72 TFLOPS FP16 at a 1:1 ratio with FP32, indicating equal FP16 and FP32 throughput. The RX 7900 GRE delivers 91.96 TFLOPS FP16 at a 2:1 ratio, meaning its FP16 throughput is double its FP32 rate. This suggests the MI308X prioritizes FP32 compute, while the RX 7900 GRE uses packed FP16 execution for graphics and compute workloads that can exploit it.

The Verdict

The data indicates two distinct products for two distinct workloads. The MI308X has no benchmark scores, no display outputs, no graphics API support, and a 750 W TDP with no power connectors on an OAM Module form factor. It is a data center accelerator designed for compute throughput, memory capacity, and memory bandwidth. The RX 7900 GRE is an active production graphics card with a 260 W TDP, dual-slot form factor, two 8-pin power connectors, a 600 W suggested PSU, and a full set of display outputs including 1x HDMI 2.1a, 2x DisplayPort 2.1, and 1x USB Type-C. Its launch MSRP is 549 USD.

Users needing graphics output, DirectX, OpenGL, or Vulkan support should select the RX 7900 GRE. The MI308X cannot output video and exposes no graphics APIs. Users needing FP32 throughput, massive memory capacity, or extremely high memory bandwidth should select the MI308X. Its 81.72 TFLOPS FP32, 192 GB HBM3, and 5.32 TB/s bandwidth are far beyond the RX 7900 GRE's 45.98 TFLOPS, 16 GB GDDR6, and 576.0 GB/s.

The RX 7900 GRE's benchmark record confirms it is a functional, competitive graphics card in the database. Its average benchmark score of 32,456 places it at the 77th percentile versus all GPUs. Its nearest rivals are the AMD FirePro S10000 at 32,388 (0.2% slower), AMD FirePro S9300 X2 at 32,540 (0.3% faster), AMD Radeon RX 590 GME at 32,601 (0.4% faster), and AMD Radeon Pro 570X at 32,176 (0.9% slower). These are all close scores, indicating the RX 7900 GRE sits in a tightly packed performance cluster. The MI308X has no nearest rivals listed and no recorded benchmarks, so its performance cannot be compared directly in the database.

FAQ

Q: Does the AMD Instinct MI308X support DirectX or Vulkan?

A: No. The database lists DirectX, OpenGL, and Vulkan as N/A for the MI308X. The Radeon RX 7900 GRE supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Q: Which card has more memory bandwidth?

A: The MI308X has 5.32 TB/s bandwidth from 192 GB of HBM3 on an 8192-bit bus. The RX 7900 GRE has 576.0 GB/s from 16 GB of GDDR6 on a 256-bit bus.

Q: What is the FP32 throughput difference?

A: The MI308X delivers 81.72 TFLOPS FP32, while the RX 7900 GRE delivers 45.98 TFLOPS. The MI308X is approximately 1.8 times higher in FP32 throughput.

Q: Which card has display outputs?

A: Only the RX 7900 GRE has display outputs: 1x HDMI 2.1a, 2x DisplayPort 2.1, and 1x USB Type-C. The MI308X lists no outputs.

Q: What are the power requirements?

A: The MI308X has a 750 W TDP with no power connectors and a suggested PSU of 1150 W. The RX 7900 GRE has a 260 W TDP, uses 2x 8-pin power connectors, and has a suggested PSU of 600 W.

Q: How does the RX 7900 GRE rank among all GPUs?

A: The RX 7900 GRE has an average benchmark score of 32,456 and sits at the 77th percentile versus all GPUs. Its nearest rival, the AMD FirePro S9300 X2, scores 32,540, which is 0.3% faster.

Head-to-Head Benchmarks

The database contains no head-to-head benchmark entries between the MI308X and the RX 7900 GRE, and the MI308X has no individual benchmark scores recorded. Direct numerical comparison is therefore impossible for actual workloads. However, specification-level data allows for meaningful comparisons in throughput and capacity.

The largest advantage for the MI308X is memory bandwidth. At 5.32 TB/s, it is roughly 9.2 times the RX 7900 GRE's 576.0 GB/s. Memory capacity differs by a factor of 12: 192 GB versus 16 GB. FP32 throughput favors the MI308X at 81.72 TFLOPS versus 45.98 TFLOPS, a margin of about 1.8 times. Texture rate also favors the MI308X at 2,553.6 GTexel/s versus 718.4 GTexel/s, a margin of about 3.6 times.

The RX 7900 GRE counters with higher clock speeds. Its base clock is 1287 MHz versus 1000 MHz, its boost clock is 2245 MHz versus 2100 MHz, and it has a game clock of 1880 MHz that the MI308X does not list. Pixel rate goes entirely to the RX 7900 GRE at 359.2 GPixel/s, since the MI308X reports 0 MPixel/s. The RX 7900 GRE also has 160 ROPs and 80 ray tracing cores, while the MI308X reports 0 ROPs and no ray tracing core count.

The RX 7900 GRE's benchmark scores provide context for its overall standing. Its highest recorded scores are 175,758 in Geekbench OpenCL and 99,850 in Geekbench Vulkan. Its 3DMark Steel Nomad DX12 score is 4,814. Passmark scores include 27,089 in G3D, 15,016 in GPU compute, 1,180 in G2D, 310 in DirectX 9, 300 in DirectX 11, 139 in DirectX 10, and 107 in DirectX 12. These scores, combined with its 77th percentile ranking, show a card that performs competitively in its peer group but does not dominate it. The nearest rivals, all within 0.9% of its average score, confirm a crowded performance tier.

Specification Differences

| Specification | AMD Instinct MI308X | AMD Radeon RX 7900 GRE |

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

| Architecture | CDNA 3.0 | RDNA 3.0 |

| Chip | Aqua Vanjaram | Navi 31 |

| Process Node | 5 nm | 5 nm |

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

| Die Size | 1017 mm² | 529 mm² |

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

| Shading Units | 19,456 | 5,120 |

| TMUs | 1,216 | 320 |

| ROPs | 0 | 160 |

| Ray Tracing Cores | Not listed | 80 |

| Base Clock | 1000 MHz | 1287 MHz |

| Boost Clock | 2100 MHz | 2245 MHz |

| Game Clock | Not listed | 1880 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 |

| FP32 | 81.72 TFLOPS | 45.98 TFLOPS |

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

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

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

| 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 |

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

| Production Status | Not listed | Active |

| Launch MSRP | Not listed | 549 USD |