AMD Instinct MI100 vs AMD Radeon RX 6600 LE Comparison

Head-to-Head Benchmarks

The only direct benchmark comparison in the database is Geekbench OpenCL, and it is a decisive victory for the AMD Instinct MI100. The MI100 scores 139,035 points, while the AMD Radeon RX 6600 LE manages 69,229 points. That is a delta of 100.8%, meaning the MI100 more than doubles the RX 6600 LE's OpenCL score. This is not a marginal gap; it is a complete performance tier separation.

The MI100's score places it in the 96th percentile of all GPUs in the database, while the RX 6600 LE sits in the 91st percentile. Both are high performers, but the MI100's raw compute output is in another class. The RX 6600 LE does have a Vulkan score of 72,428, but the MI100 has no recorded Vulkan result, so no cross-API comparison is possible from the data.

Looking at nearest rivals, the MI100 edges out the NVIDIA Tesla V100 PCIe 16 GB by 0.7%, the Tesla V100 SXM2 32 GB by 0.9%, the AMD Radeon PRO V620 by 1.9%, and the AMD Radeon Pro W6800X Duo by 2.4%. These are close margins, which positions the MI100 as a strong but not overwhelming leader in its compute segment. The RX 6600 LE, by contrast, sits 1% ahead of the NVIDIA RTX A3000 Mobile, 1.2% ahead of the Quadro P6000, and 1.4% ahead of the AMD Radeon Pro WX 8200, but it trails the AMD Radeon RX 6650M by 1.3%. This shows the RX 6600 LE is competitive with mobile and workstation parts, but it does not dominate its category the way the MI100 does.

The database records one win for the MI100 and zero for the RX 6600 LE in head-to-head tests. That is a clean sweep, but the context matters: the MI100 is built for compute workloads, while the RX 6600 LE targets a different use case, which the following sections clarify.

Architecture Differences

The MI100 uses the Arcturus chip built on CDNA 1.0 architecture, while the RX 6600 LE uses the Navi 23 chip built on RDNA 2.0. Both are manufactured by TSMC on a 7 nm process, but the similarities end there. CDNA 1.0 is optimized for compute and server workloads, while RDNA 2.0 is designed for graphics and gaming.

The transistor counts differ dramatically. The MI100 packs 25,600 million transistors on a 750 mm² die, giving it a transistor density of 34.1 million per mm². The RX 6600 LE has 11,060 million transistors on a 237 mm² die, with a higher density of 46.7 million per mm². In simple terms, the MI100 is a much larger chip with more raw resources, while the RX 6600 LE is a smaller, denser design that achieves better efficiency per square millimeter.

Memory configurations are also fundamentally different. The MI100 uses 32 GB of HBM2 with a 4096-bit bus and 1.23 TB/s bandwidth. The RX 6600 LE uses 8 GB of GDDR6 with a 128-bit bus and 224.0 GB/s bandwidth. The MI100's memory bandwidth is over five times higher, which directly impacts compute-heavy workloads that saturate memory. The RX 6600 LE's smaller memory pool and narrower bus reflect its consumer-oriented design.

The compute units tell the same story. The MI100 has 7,680 shading units, 480 texture mapping units, and 64 ROPs. The RX 6600 LE has 1,792 shading units, 112 TMUs, and 64 ROPs. While the ROP count is identical, the MI100 has 4.3 times the shading units and 4.3 times the TMUs. This explains the massive FP32 performance gap: the MI100 delivers 23.07 TFLOPS versus 8.942 TFLOPS for the RX 6600 LE. FP16 follows the same pattern at 46.14 TFLOPS versus 17.88 TFLOPS.

Clock speeds favor the RX 6600 LE. Its base clock is 1626 MHz with a boost up to 2495 MHz, while the MI100 runs at 1000 MHz base and 1502 MHz boost. The RX 6600 LE also has a game clock of 2045 MHz. Higher clocks help the RX 6600 LE close some gap in graphics workloads, but they cannot compensate for the MI100's massive resource advantage in compute.

The RX 6600 LE has 28 ray tracing cores, a feature the MI100 completely lacks. The MI100 has no RT cores, no display outputs, and no graphics API support (DirectX, OpenGL, and Vulkan are all listed as N/A). The RX 6600 LE supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, along with display outputs including 1x HDMI 2.1 and 3x DisplayPort 1.4a. This is a clear split: the MI100 is a compute accelerator with no graphics output, while the RX 6600 LE is a full graphics card.

Where Each One Wins

The MI100 wins in pure compute performance, memory capacity, and memory bandwidth. Its 139,035 OpenCL score is 100.8% higher than the RX 6600 LE's 69,229. Any workload that relies on massive parallel FP32 or FP16 throughput, such as scientific simulation, AI inference, or data center processing, will favor the MI100. The 32 GB HBM2 pool with 1.23 TB/s bandwidth means it can handle datasets far larger than the RX 6600 LE's 8 GB GDDR6 with 224.0 GB/s. The MI100's 23.07 TFLOPS FP32 and 46.14 TFLOPS FP16 are simply in a different league.

The RX 6600 LE wins in graphics-focused scenarios. It has ray tracing cores, full DirectX 12 Ultimate support, and display outputs. Its higher clock speeds, with a boost of 2495 MHz, contribute to a pixel rate of 159.7 GPixel/s, which actually exceeds the MI100's 96.13 GPixel/s despite the MI100 having far more shading units. The RX 6600 LE also has a texture rate of 279.4 GTexel/s, though that is lower than the MI100's 721.0 GTexel/s. For gaming, desktop rendering, or any workload requiring visual output, the RX 6600 LE is the only viable option because the MI100 has no display outputs at all.

The RX 6600 LE also wins on power efficiency in practical terms. It has a TDP of 132 W with a suggested PSU of 300 W, while the MI100 has a TDP of 300 W and requires a 700 W PSU. The RX 6600 LE uses 1x 8-pin power connector versus 2x 8-pin for the MI100. Lower power draw and simpler power delivery make the RX 6600 LE easier to deploy in standard systems.

FAQ

Q: Which GPU has the higher OpenCL benchmark score?

A: The AMD Instinct MI100 scores 139,035 in Geekbench OpenCL, which is 100.8% higher than the AMD Radeon RX 6600 LE's score of 69,229.

Q: Does the RX 6600 LE support ray tracing?

A: Yes, it has 28 ray tracing cores. The MI100 has no RT cores and no graphics API support, with DirectX, OpenGL, and Vulkan all listed as N/A.

Q: What are the memory specifications of each card?

A: The MI100 has 32 GB of HBM2 on a 4096-bit bus with 1.23 TB/s bandwidth. The RX 6600 LE has 8 GB of GDDR6 on a 128-bit bus with 224.0 GB/s bandwidth.

Q: Can the MI100 output video to a display?

A: No, the MI100 has no display outputs. The RX 6600 LE has 1x HDMI 2.1 and 3x DisplayPort 1.4a outputs.

Q: How do their power requirements compare?

A: The MI100 has a TDP of 300 W and needs a 700 W PSU, while the RX 6600 LE has a TDP of 132 W and needs a 300 W PSU. The MI100 uses 2x 8-pin connectors, the RX 6600 LE uses 1x 8-pin.

Q: Which GPU has the higher clock speed?

A: The RX 6600 LE boosts to 2495 MHz, while the MI100 boosts to 1502 MHz. The RX 6600 LE also has a base clock of 1626 MHz versus 1000 MHz for the MI100.

Specification Differences

The two cards differ in nearly every major specification. The MI100 uses the Arcturus chip on CDNA 1.0, while the RX 6600 LE uses Navi 23 on RDNA 2.0. Transistor counts are 25,600 million versus 11,060 million. Die sizes are 750 mm² versus 237 mm². Transistor density is 34.1M per mm² versus 46.7M per mm².

Clocks: The MI100 has a 1000 MHz base and 1502 MHz boost, while the RX 6600 LE has a 1626 MHz base, 2045 MHz game clock, and 2495 MHz boost. Memory clocks are 1200 MHz (2.4 Gbps effective) for the MI100 versus 1750 MHz (14 Gbps effective) for the RX 6600 LE.

Memory: The MI100 has 32 GB HBM2 on a 4096-bit bus with 1.23 TB/s bandwidth. The RX 6600 LE has 8 GB GDDR6 on a 128-bit bus with 224.0 GB/s bandwidth.

Compute resources: The MI100 has 7,680 shading units, 480 TMUs, and 64 ROPs. The RX 6600 LE has 1,792 shading units, 112 TMUs, 64 ROPs, and 28 RT cores. The MI100 has no RT cores.

Performance rates: The MI100 delivers 96.13 GPixel/s, 721.0 GTexel/s, 23.07 TFLOPS FP32, and 46.14 TFLOPS FP16. The RX 6600 LE delivers 159.7 GPixel/s, 279.4 GTexel/s, 8.942 TFLOPS FP32, and 17.88 TFLOPS FP16.

Power: The MI100 has a 300 W TDP, 2x 8-pin connectors, and a 700 W suggested PSU. The RX 6600 LE has a 132 W TDP, 1x 8-pin connector, and a 300 W suggested PSU.

Form and connectivity: The MI100 has no display outputs and uses PCIe 4.0 x16. The RX 6600 LE has 1x HDMI 2.1 and 3x DisplayPort 1.4a and uses PCIe 4.0 x8. The MI100 is 267 mm long and 111 mm tall, while the RX 6600 LE is 190 mm long, 110 mm tall, and 40 mm wide.

APIs: The MI100 lists DirectX, OpenGL, and Vulkan as N/A. The RX 6600 LE supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4.

Production status: The MI100 is end-of-life with a release date of 2020-11-15. The RX 6600 LE is active with a release date of 2023-12-07.

The Verdict

The data is unambiguous for compute workloads. The AMD Instinct MI100 is the superior compute accelerator. Its 139,035 OpenCL score doubles that of the RX 6600 LE, and its 32 GB HBM2 memory with 1.23 TB/s bandwidth dwarfs the 8 GB GDDR6 at 224.0 GB/s. The MI100's 23.07 TFLOPS FP32 and 46.14 TFLOPS FP16 are more than double the RX 6600 LE's figures. Any task that stresses raw math throughput, large datasets, or memory bandwidth belongs on the MI100. It sits in the 96th percentile of all GPUs, and its closest rivals are Tesla V100 variants that it beats by less than 1%, confirming it is a top-tier compute part.

The AMD Radeon RX 6600 LE is the correct choice for graphics and desktop use. It has ray tracing cores, full DirectX 12 Ultimate support, Vulkan 1.4, and display outputs. Its higher clock speeds deliver a pixel rate of 159.7 GPixel/s, which beats the MI100's 96.13 GPixel/s. The RX 6600 LE also draws 132 W versus 300 W, making it far easier to power and cool. Its 91st percentile standing among all GPUs is respectable, and its Vulkan score of 72,428 shows solid graphics API performance.

The verdict depends entirely on the intended workload. For a server, research cluster, or compute pipeline, the MI100 is the obvious choice. For a gaming PC, workstation with graphics needs, or any system requiring video output, the RX 6600 LE is the only option that makes sense. The MI100 cannot display anything, so it is not a general-purpose GPU. The RX 6600 LE cannot match the MI100's compute throughput, so it is not a data center accelerator. The database records one head-to-head win for the MI100, and that win reflects the compute-centric benchmark used. No graphics benchmark exists in the data, so the RX 6600 LE's advantages in that domain are qualitative rather than quantified. The user should pick based on whether they need compute density or graphics capability, as the two cards are not interchangeable.