AMD Instinct MI308X vs AMD Radeon RX 6600 LE Comparison

Head-to-Head Benchmarks

The recorded database does not contain any direct head-to-head benchmark comparisons between the AMD Instinct MI308X and the AMD Radeon RX 6600 LE. The head-to-head benchmark array is empty, and neither product has a wins counter populated. This means there is no measured performance data where both products ran identical workloads under the same test conditions.

What the database does contain is a single benchmark entry for the RX 6600 LE, which reports an average benchmark score of 70,829 across two tests: Geekbench OpenCL at 69,229 and Geekbench Vulkan at 72,428. The MI308X, by contrast, has no benchmark entries at all, and its average benchmark score is recorded as zero. Its percentile versus all GPUs is 50, while the RX 6600 LE sits at the 91st percentile.

The absence of data for the MI308X is itself informative. The database shows no measured workloads for this accelerator, which limits any quantitative comparison. For the RX 6600 LE, the nearest rival data provides context: it trails the AMD Radeon RX 6650M by 1.3 percent (rival average score 71,768), and it leads the NVIDIA RTX A3000 Mobile by 1 percent (70,140), the NVIDIA Quadro P6000 by 1.2 percent (69,986), and the AMD Radeon Pro WX 8200 by 1.4 percent (69,870). These deltas are small, placing the RX 6600 LE in a tight competitive cluster among mobile and workstation GPUs.

Without head-to-head numbers, any cross-product score comparison would be speculative. The database simply lacks the measured data to state which product wins in a given workload.

Architecture Differences

The two accelerators share a manufacturer but diverge sharply in architecture, process technology, and design goals. The MI308X uses the CDNA 3.0 architecture on the Aqua Vanjaram chip, built on a 5 nm process at TSMC. The RX 6600 LE uses RDNA 2.0 on the Navi 23 chip, built on a 7 nm process, also at TSMC. The MI308X belongs to the Instinct (MIx) generation, while the RX 6600 LE belongs to the Radeon RX 6000 series, generation Navi II.

Transistor counts differ by an order of magnitude. The MI308X packs 153,000 million transistors on a 1017 mm² die, yielding a transistor density of 150.4 million per mm². The RX 6600 LE contains 11,060 million transistors on a 237 mm² die, with a density of 46.7 million per mm². The MI308X die is roughly four times larger and carries nearly fourteen times the transistor count.

Memory subsystems are fundamentally different. The MI308X uses 192 GB of HBM3 on an 8192 bit bus, delivering 5.32 TB/s of bandwidth. The RX 6600 LE uses 8 GB of GDDR6 on a 128 bit bus, delivering 224.0 GB/s. The MI308X memory clock is listed at 1300 MHz with 5.2 Gbps effective, while the RX 6600 LE memory runs at 1750 MHz with 14 Gbps effective. The bandwidth gap is roughly 24 to 1 in favor of the MI308X.

Compute resources also diverge. The MI308X has 19,456 shading units, 1,216 texture mapping units, and zero ROPs. Its pixel rate is recorded as 0 MPixel/s, and its texture rate is 2,553.6 GTexel/s. The RX 6600 LE has 1,792 shading units, 112 TMUs, and 64 ROPs, with a pixel rate of 159.7 GPixel/s and a texture rate of 279.4 GTexel/s. The MI308X also has no RT cores listed, while the RX 6600 LE includes 28 RT cores.

Floating point performance shows the intended use case. The MI308X delivers 81.72 TFLOPS for both FP32 and FP16, at a 1:1 ratio. The RX 6600 LE delivers 8.942 TFLOPS for FP32 and 17.88 TFLOPS for FP16, at a 2:1 ratio. The MI308X has roughly nine times the FP32 throughput, but the RX 6600 LE offers a more conventional consumer ratio where FP16 doubles the FP32 rate.

Power and physical design differ completely. The MI308X carries a 750 W TDP with a suggested PSU of 1150 W, uses an OAM module slot width, has no power connectors listed, and has no display outputs. The RX 6600 LE has a 132 W TDP with a suggested PSU of 300 W, uses a dual-slot design, takes a single 8-pin power connector, and offers display outputs of 1x HDMI 2.1 and 3x DisplayPort 1.4a. The MI308X measures no dimensions in the database, while the RX 6600 LE is 190 mm long, 110 mm tall, and 40 mm wide.

Bus interfaces also differ: the MI308X uses PCIe 5.0 x16, while the RX 6600 LE uses PCIe 4.0 x8. API support is absent for the MI308X, with DirectX, OpenGL, and Vulkan all listed as N/A. The RX 6600 LE supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Where Each One Wins

The MI308X wins decisively in raw compute density, memory capacity, and memory bandwidth. Its 192 GB HBM3 pool with 5.32 TB/s bandwidth is built for data-scale workloads that exceed the 8 GB GDDR6 frame buffer of the RX 6600 LE by a factor of 24. Its FP32 throughput of 81.72 TFLOPS dwarfs the 8.942 TFLOPS of the RX 6600 LE, making it suitable for large matrix operations and simulation tasks that can saturate thousands of shading units.

The RX 6600 LE wins in conventional graphics output. It has 64 ROPs with a pixel rate of 159.7 GPixel/s, whereas the MI308X has zero ROPs and a pixel rate of zero. The RX 6600 LE also includes 28 RT cores and full API support for DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, none of which exist on the MI308X. Display outputs are present on the RX 6600 LE, while the MI308X has none. For any workload that requires rasterization, ray tracing, or driving a monitor, the RX 6600 LE is the only viable option.

The RX 6600 LE also wins on efficiency in the measured data. Its 132 W TDP is far lower than the 750 W TDP of the MI308X, and its suggested PSU of 300 W versus 1150 W reflects a much smaller system footprint. Its dual-slot form factor and single 8-pin connector make it adaptable to standard PC builds, while the MI308X requires an OAM module slot with no power connector specification.

The benchmark record favors the RX 6600 LE simply because it has one. Its Geekbench OpenCL score of 69,229 and Vulkan score of 72,428 place it at the 91st percentile among all GPUs. The MI308X has no recorded benchmark scores and sits at the 50th percentile by default, which reflects a lack of data rather than measured performance.

FAQ

Q: Does the AMD Instinct MI308X have any benchmark scores in the database?

A: No. The MI308X has an empty benchmark array, an average benchmark score of 0, and no nearest rival entries. The RX 6600 LE has two recorded scores: Geekbench OpenCL at 69,229 and Geekbench Vulkan at 72,428.

Q: Which product has more memory bandwidth?

A: The MI308X delivers 5.32 TB/s across an 8192 bit HBM3 bus. The RX 6600 LE delivers 224.0 GB/s across a 128 bit GDDR6 bus. The MI308X bandwidth is roughly 24 times higher.

Q: Can the MI308X output video to a display?

A: No. The MI308X lists no display outputs, and its pixel rate is recorded as 0 MPixel/s with zero ROPs. The RX 6600 LE has 1x HDMI 2.1 and 3x DisplayPort 1.4a outputs.

Q: What is the FP32 performance difference?

A: The MI308X delivers 81.72 TFLOPS of FP32. The RX 6600 LE delivers 8.942 TFLOPS. This makes the MI308X approximately nine times faster in raw FP32 throughput.

Q: Which product supports ray tracing?

A: The RX 6600 LE includes 28 RT cores and supports DirectX 12 Ultimate (12_2), which includes ray tracing features. The MI308X lists no RT cores and has N/A for DirectX, OpenGL, and Vulkan support.

Q: What is the transistor density difference?

A: The MI308X has a transistor density of 150.4 million per mm² on a 5 nm process. The RX 6600 LE has a density of 46.7 million per mm² on a 7 nm process. Both are fabricated by TSMC.

Specification Differences

The database records the following differences between the two products:

• Chip: Aqua Vanjaram (MI308X) versus Navi 23 (RX 6600 LE)
• Architecture: CDNA 3.0 versus RDNA 2.0
• Generation: Instinct (MIx) versus Navi II (RX 6000)
• Process node: 5 nm versus 7 nm
• Transistors: 153,000 million versus 11,060 million
• Die size: 1017 mm² versus 237 mm²
• Transistor density: 150.4M / mm² versus 46.7M / mm²
• Base clock: 1000 MHz versus 1626 MHz
• Boost clock: 2100 MHz versus 2495 MHz
• Game clock: not listed versus 2045 MHz
• Memory clock: 1300 MHz 5.2 Gbps effective versus 1750 MHz 14 Gbps effective
• Memory size: 192 GB versus 8 GB
• Memory type: HBM3 versus GDDR6
• Memory bus width: 8192 bit versus 128 bit
• Memory bandwidth: 5.32 TB/s versus 224.0 GB/s
• Shading units: 19,456 versus 1,792
• TMUs: 1,216 versus 112
• ROPs: 0 versus 64
• RT cores: not listed versus 28
• Pixel rate: 0 MPixel/s versus 159.7 GPixel/s
• Texture rate: 2,553.6 GTexel/s versus 279.4 GTexel/s
• FP32: 81.72 TFLOPS versus 8.942 TFLOPS
• FP16: 81.72 TFLOPS (1:1) versus 17.88 TFLOPS (2:1)
• TDP: 750 W versus 132 W
• Slot width: OAM Module versus Dual-slot
• Power connectors: None versus 1x 8-pin
• Suggested PSU: 1150 W versus 300 W
• Bus interface: PCIe 5.0 x16 versus PCIe 4.0 x8
• Display outputs: No outputs versus 1x HDMI 2.13x DisplayPort 1.4a
• APIs: DirectX, OpenGL, Vulkan all N/A versus DirectX 12 Ultimate (12_2), OpenGL 4.6, Vulkan 1.4
• Dimensions: not listed versus 190 mm x 110 mm x 40 mm
• Production status: not listed versus Active
• Release date: 2023-12-05 versus 2023-12-07
• Predecessor: Radeon Instinct versus Navi
• Successor: not listed versus Navi III

The Verdict

The data presents two products with no overlapping use cases. The MI308X is a compute accelerator with no display output, no rasterization hardware, and no consumer API support. Its 192 GB HBM3 memory, 5.32 TB/s bandwidth, and 81.72 TFLOPS FP32 rate target server-scale workloads where graphics output is irrelevant. The RX 6600 LE is a conventional graphics card with 64 ROPs, 28 RT cores, full DirectX 12 Ultimate support, and display outputs, built to render frames and push pixels.

For a user selecting between these two, the decision should rest on whether the workload requires rendering or compute. The RX 6600 LE is the only option that can drive a monitor, run ray-traced content, or use standard graphics APIs. Its 91st percentile benchmark standing and active production status confirm it as a functioning consumer product. The MI308X, with no benchmark scores and no graphics pipeline, exists for a different purpose entirely.

The MI308X wins on every compute metric in the specification table, but those metrics come with a 750 W TDP, an OAM module form factor, and zero graphics functionality. The RX 6600 LE wins on every graphics metric, at a fraction of the power draw, in a standard dual-slot card. The database offers no head-to-head benchmark results, so the verdict rests on architectural intent. Choose the MI308X for massive memory and compute throughput in non-rendered environments. Choose the RX 6600 LE for any task that produces visible frames.