AMD Radeon RX 6600 LE vs NVIDIA CMP 40HX Comparison

# NVIDIA CMP 40HX vs AMD Radeon RX 6600 LE

The NVIDIA CMP 40HX and AMD Radeon RX 6600 LE occupy different corners of the GPU landscape, with the former built for mining workloads and the latter designed as a mainstream Radeon part. Benchmark data shows the CMP 40HX holds a clear performance edge in both tested workloads, but the RX 6600 LE counters with superior efficiency and modern connectivity. The CMP 40HX averages 85,637 across its benchmark suite, placing it in the 93rd percentile of all GPUs, while the RX 6600 LE averages 70,829, sitting in the 91st percentile. These are close percentile rankings, yet the raw score gap tells a more nuanced story about workload-specific strengths.

The Verdict

The data paints a straightforward picture for most buyers. The NVIDIA CMP 40HX wins both head-to-head benchmark comparisons decisively, delivering a 34.9% higher Geekbench OpenCL score and a 7.5% higher Vulkan score than the RX 6600 LE. Anyone prioritizing raw compute throughput in OpenCL-heavy applications should choose the CMP 40HX without hesitation. Its average benchmark score of 85,637 places it 20.9% above the RX 6600 LE's 70,829 average, a substantial margin that persists across both tested workloads.

However, the RX 6600 LE is the more practical choice for general-purpose use. It draws 132 W versus 185 W for the CMP 40HX, requires a 300 W power supply versus 450 W, and includes display outputs (1x HDMI 2.1, 3x DisplayPort 1.4a) whereas the CMP 40HX has no outputs at all. The CMP 40HX is end-of-life production with a launch MSRP of 699 USD, while the RX 6600 LE remains active in production. For gamers or workstation users needing a display connection, the RX 6600 LE is the only viable option despite its lower scores. For compute-focused deployments where display output is irrelevant, the CMP 40HX's benchmark superiority makes it the clear winner.

Architecture Differences

The two GPUs come from fundamentally different architectures and manufacturing processes. NVIDIA's CMP 40HX uses the TU106 chip based on Turing architecture, built on TSMC's 12 nm process. It packs 10,800 million transistors across a 445 mm² die, yielding a transistor density of 24.3 million per mm². AMD's RX 6600 LE employs the Navi 23 chip with RDNA 2.0 architecture, fabricated on TSMC's 7 nm node. It contains 11,060 million transistors on a much smaller 237 mm² die, achieving 46.7 million transistors per mm²—nearly double the density of the Turing chip.

The CMP 40HX features 2,304 shading units, 144 texture mapping units, and 64 ROPs, complemented by 36 ray tracing cores and 288 tensor cores. The RX 6600 LE counters with 1,792 shading units, 112 TMUs, and 64 ROPs, plus 28 ray tracing cores but no tensor cores. Clock speeds favor AMD significantly: the RX 6600 LE boosts to 2495 MHz with a 2045 MHz game clock and 1626 MHz base, while the CMP 40HX boosts to 1650 MHz with a 1470 MHz base. Despite fewer shading units, the RX 6600 LE's higher clocks push its FP32 throughput to 8.942 TFLOPS, exceeding the CMP 40HX's 7.603 TFLOPS. The RX 6600 LE also leads in texture rate at 279.4 GTexel/s versus 237.6 GTexel/s.

Memory configurations diverge sharply. Both cards use 8 GB of GDDR6, but the CMP 40HX employs a 256-bit bus delivering 448.0 GB/s bandwidth, while the RX 6600 LE uses a 128-bit bus halving bandwidth to 224.0 GB/s. The CMP 40HX's wider memory bus is a key factor in its compute advantage. Bus interface differs too: the CMP 40HX uses PCIe 1.0 x4, an unusual choice reflecting its mining origins, while the RX 6600 LE uses modern PCIe 4.0 x8. Both cards support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Head-to-Head Benchmarks

The Geekbench OpenCL test delivers the largest performance gap between these two GPUs. The NVIDIA CMP 40HX scores 93,395, while the AMD Radeon RX 6600 LE manages 69,229—a 34.9% difference in favor of NVIDIA. This substantial margin likely reflects the CMP 40HX's 448.0 GB/s memory bandwidth and 256-bit bus, which provide a significant advantage in memory-intensive compute workloads. The CMP 40HX's 7.603 TFLOPS FP32 throughput, while lower than the RX 6600 LE's 8.942 TFLOPS, is paired with nearly double the memory bandwidth, enabling more efficient data movement during OpenCL execution.

The Vulkan test narrows the gap considerably. The CMP 40HX scores 77,879 versus 72,428 for the RX 6600 LE, a 7.5% advantage. This closer margin suggests that Vulkan workloads benefit more from the RX 6600 LE's higher clock speeds and modern RDNA 2.0 architecture, partially offsetting the memory bandwidth deficit. Still, the CMP 40HX maintains its winning streak across both tests, securing two wins in the head-to-head comparison with zero for the RX 6600 LE.

Against their respective nearest rivals, both cards hold their ground. The CMP 40HX trails the AMD Radeon PRO W7600 by 1.7% and the NVIDIA Quadro GP100 by 2.1%, while leading the AMD Radeon PRO W6600 by 4.4% and the AMD Radeon Pro Vega 64X by 5.8%. The RX 6600 LE edges the NVIDIA RTX A3000 Mobile by 1% and the NVIDIA Quadro P6000 by 1.2%, while falling 1.3% short of the AMD Radeon RX 6650M and leading the AMD Radeon Pro WX 8200 by 1.4%. These tight margins indicate both GPUs sit in a competitive mid-range performance tier.

FAQ

Q: Which GPU has higher raw compute performance?

A: The NVIDIA CMP 40HX achieves higher benchmark scores in both tested workloads, with an average benchmark score of 85,637 compared to the RX 6600 LE's 70,829. It wins Geekbench OpenCL by 34.9% and Vulkan by 7.5%.

Q: Does the RX 6600 LE have better specifications in any area?

A: Yes. The RX 6600 LE has higher clock speeds (2495 MHz boost versus 1650 MHz), higher FP32 throughput (8.942 TFLOPS versus 7.603 TFLOPS), faster texture rate (279.4 GTexel/s versus 237.6 GTexel/s), and a more advanced 7 nm process node.

Q: Why does the CMP 40HX win benchmarks despite lower clock speeds?

A: The CMP 40HX has double the memory bandwidth (448.0 GB/s versus 224.0 GB/s) and a 256-bit memory bus versus 128-bit, which likely provides a significant advantage in memory-intensive compute workloads like OpenCL.

Q: Can these GPUs be used for gaming or display output?

A: The RX 6600 LE includes display outputs (1x HDMI 2.1 and 3x DisplayPort 1.4a), making it suitable for gaming. The CMP 40HX has no display outputs and is designed exclusively for mining workloads.

Q: How do their power requirements compare?

A: The RX 6600 LE has a lower TDP of 132 W and requires a 300 W power supply, while the CMP 40HX has a 185 W TDP and requires a 450 W power supply. Both use a single 8-pin power connector.

Q: Which GPU is more recent?

A: The RX 6600 LE was released on 2023-12-07 and remains in active production, while the CMP 40HX was released on 2021-02-24 and is end-of-life.

Where Each One Wins

The NVIDIA CMP 40HX dominates in raw compute benchmarks, and this advantage is most pronounced in OpenCL workloads. Its 34.9% lead in Geekbench OpenCL makes it the clear choice for compute-heavy applications that leverage OpenCL acceleration, such as scientific simulations, data processing, or rendering tasks that rely on this API. The 448.0 GB/s memory bandwidth and 256-bit bus provide the data throughput necessary for large datasets, and the 8 GB GDDR6 frame buffer matches the RX 6600 LE's capacity while offering superior bandwidth. The CMP 40HX also wins in Vulkan performance, though by a narrower 7.5% margin, indicating it retains an edge even in more modern graphics APIs. Its 93rd percentile ranking versus 91st for the RX 6600 LE confirms its position slightly higher in the overall GPU hierarchy.

The AMD Radeon RX 6600 LE wins in efficiency and practical usability. Its 132 W TDP represents a 28.6% reduction in power draw compared to the CMP 40HX's 185 W, and its 300 W recommended power supply is 33.3% lower than the CMP 40HX's 450 W requirement. This makes it substantially cheaper to operate and easier to integrate into existing systems without power supply upgrades. The RX 6600 LE's modern PCIe 4.0 x8 interface provides superior connectivity versus the CMP 40HX's legacy PCIe 1.0 x4, and its display outputs enable use in gaming, content creation, or general desktop environments where the CMP 40HX cannot function. The higher boost clock of 2495 MHz and FP32 throughput of 8.942 TFLOPS also suggest the RX 6600 LE may offer better performance in workloads sensitive to clock speed and shader throughput rather than memory bandwidth. Its 7 nm process node and higher transistor density (46.7M per mm² versus 24.3M per mm²) indicate a more modern, efficient design that remains in active production with ongoing support. For power-conscious users, gamers, or anyone requiring display output, the RX 6600 LE is the clear winner despite its benchmark deficit.