AMD Radeon RX 6600M vs NVIDIA GeForce RTX 2080 Comparison

The Verdict

The benchmark data is unambiguous: the NVIDIA GeForce RTX 2080 wins every single head-to-head test against the AMD Radeon RX 6600M, taking all 10 comparisons. The largest margin comes in Geekbench Vulkan, where the RTX 2080 leads by 31.6%, and the smallest in Passmark DirectX 11, where it leads by 13.9%. The RX 6600M never once closes the gap to within single digits. For anyone selecting purely on measured performance, the RTX 2080 is the clear choice across every workload represented in the data.

However, the context matters. The RX 6600M is a mobile part with a 100 W TDP and an IGP slot width, while the RTX 2080 is a dual-slot desktop card with a 215 W TDP and a 550 W suggested PSU. The RTX 2080 also carries a launch MSRP of 699 USD. The RX 6600M consumes less than half the power and requires no power connectors, making it the only viable option for thin-and-light portable systems. The data shows the RTX 2080 is faster, but the RX 6600M is the only one of the two that fits in a mobile form factor. The verdict depends entirely on whether the system is a laptop or a desktop; for raw performance, the RTX 2080, for portability, the RX 6600M.

FAQ

Q: Which GPU has the higher average benchmark score?

A: The AMD Radeon RX 6600M has a higher average benchmark score of 23273, compared to the NVIDIA GeForce RTX 2080's 22895. This average is computed across all tests, but in direct head-to-head comparisons the RTX 2080 wins every time.

Q: How much faster is the RTX 2080 in DirectX 12 Ultimate workloads?

A: In the 3DMark Steel Nomad DX12 test, the RTX 2080 scores 1752 versus the RX 6600M's 1495, a 14.7% advantage. Both GPUs support DirectX 12 Ultimate (12_2), but the NVIDIA part delivers higher frame throughput in this specific benchmark.

Q: Does the RX 6600M outperform the RTX 2080 in any compute workload?

A: No. The data shows the RTX 2080 wins all compute-related tests, including Geekbench OpenCL (91313 vs 67765, a 25.8% lead) and Passmark GPU Compute (7872 vs 5646, a 28.3% lead). The RX 6600M has zero wins across all 10 head-to-head benchmarks.

Q: What is the transistor density difference between the two chips?

A: The RX 6600M's Navi 23 chip has a transistor density of 46.7M per mm², while the RTX 2080's TU104 chip has 25.0M per mm². The AMD chip is built on a 7 nm process versus 12 nm for NVIDIA, but the RTX 2080 still has more total transistors (13,600 million vs 11,060 million).

Q: How do the memory subsystems compare?

A: Both have 8 GB of GDDR6 memory and the same 1750 MHz memory clock (14 Gbps effective). The RTX 2080 uses a 256-bit bus yielding 448.0 GB/s bandwidth, while the RX 6600M uses a 128-bit bus yielding 224.0 GB/s—exactly half the bandwidth.

Q: Which GPU has a higher pixel rate despite being slower overall?

A: The RX 6600M has a pixel rate of 154.6 GPixel/s, which is higher than the RTX 2080's 109.4 GPixel/s. This is an anomaly in the data: despite lower overall benchmark scores, the AMD part has a higher pixel throughput, likely due to its higher boost clock of 2416 MHz versus 1710 MHz.

Architecture Differences

The two GPUs come from entirely different design philosophies. The AMD Radeon RX 6600M uses the Navi 23 chip built on RDNA 2.0 architecture, manufactured on a 7 nm process at TSMC. The NVIDIA GeForce RTX 2080 uses the TU104 chip built on Turing architecture, manufactured on a 12 nm process, also at TSMC. The node difference is significant: AMD packs 11,060 million transistors into a 237 mm² die, yielding a density of 46.7M per mm². NVIDIA packs 13,600 million transistors into a much larger 545 mm² die, yielding only 25.0M per mm². The RTX 2080 has more raw silicon, but the RX 6600M is far more efficient in density.

Both architectures support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The key architectural split is in the compute and ray tracing units. The RX 6600M has 1792 shading units, 112 texture mapping units, 64 ROPs, and 28 ray tracing cores. The RTX 2080 has 2944 shading units, 184 TMUs, 64 ROPs, 46 ray tracing cores, and 368 tensor cores. The NVIDIA part has a substantial lead in shading units (64% more), TMUs (64% more), and ray tracing cores (64% more). The RX 6600M has no tensor cores at all, while the RTX 2080 includes them, which affects AI-accelerated workloads.

The memory architecture differs as well. Both use 8 GB of GDDR6, but the RTX 2080's 256-bit bus provides 448.0 GB/s of bandwidth, double the 224.0 GB/s of the RX 6600M's 128-bit bus. The clock speeds favor AMD: the RX 6600M has a base clock of 2068 MHz and boost of 2416 MHz, while the RTX 2080 runs at 1515 MHz base and 1710 MHz boost. The AMD part's higher clocks partially compensate for fewer cores, but not enough to overcome the NVIDIA part's raw resources.

Specification Differences

The most striking specification differences are in power and physical form. The RX 6600M has a TDP of 100 W and is classified as IGP (integrated graphics processor) with no power connectors, while the RTX 2080 has a TDP of 215 W, is dual-slot, and requires 1x 6-pin plus 1x 8-pin power connectors with a 550 W suggested PSU. The RX 6600M's bus interface is PCIe 4.0 x8, while the RTX 2080 uses PCIe 3.0 x16. The AMD part has no listed dimensions, while the RTX 2080 measures 267 mm in length, 116 mm in height, and 35 mm in width.

The compute specifications show a clear hierarchy. The RTX 2080 has 2944 shading units versus 1792, 184 TMUs versus 112, and 46 ray tracing cores versus 28. The ROP count is identical at 64. Floating-point performance favors NVIDIA: 10.07 TFLOPS FP32 versus 8.659 TFLOPS, and 20.14 TFLOPS FP16 versus 17.32 TFLOPS (both at 2:1 ratio). Texture rate also favors NVIDIA at 314.6 GTexel/s versus 270.6 GTexel/s, but pixel rate favors AMD at 154.6 GPixel/s versus 109.4 GPixel/s.

Both are end-of-life products. The RX 6600M was released on 2021-05-30, while the RTX 2080 was released earlier on 2018-09-19. The RTX 2080 has a launch MSRP of 699 USD; the RX 6600M has no launch MSRP listed. The RTX 2080's predecessor is GeForce 10 and its successor is GeForce 30, while the RX 6600M's predecessor is Polaris Mobile with no successor listed. Display outputs differ: the RX 6600M is portable-device dependent, while the RTX 2080 has 1x HDMI 2.0, 3x DisplayPort 1.4a, and 1x USB Type-C.

Head-to-Head Benchmarks

The RTX 2080 dominates every benchmark, but the margins vary meaningfully. The biggest win is in Geekbench Vulkan, where the RTX 2080 scores 107797 against the RX 6600M's 73740, a 31.6% advantage. This is the largest gap in the entire dataset. The second largest is in Passmark DirectX 10, where the RTX 2080 leads by 36% (136 versus 87). Geekbench OpenCL shows a 25.8% lead (91313 versus 67765), and Passmark GPU Compute shows a 28.3% lead (7872 versus 5646).

In DirectX 11, the RTX 2080's advantage narrows to 13.9% (158 versus 136). In DirectX 12, the lead grows to 27.8% (72 versus 52). In DirectX 9, the RTX 2080 leads by 17.5% (223 versus 184). The 3DMark Steel Nomad DX12 test shows a 14.7% lead (1752 versus 1495). Passmark G2D shows a 19.7% lead (907 versus 728), and Passmark G3D shows a 25.6% lead (18720 versus 13929).

The RX 6600M's best relative showing is in Passmark DirectX 11, where it trails by only 13.9%. Its worst is in Passmark DirectX 10, where it trails by 36%. Notably, the RX 6600M's average benchmark score of 23273 is actually higher than the RTX 2080's 22895, despite losing every direct comparison. This discrepancy arises because the average includes different test suites, and the RX 6600M's nearest rivals include the AMD Radeon R9 M290X (23276, 0% delta) and AMD Radeon Pro Vega 16 (23250, 0.1% delta), while the RTX 2080's nearest rivals include the NVIDIA GeForce RTX 3080 (23172, -1.2% delta) and Intel Arc B580 (23021, -0.5% delta). The RTX 2080's percentile rank is 68, identical to the RX 6600M's 68, placing both in the same overall performance tier despite the RTX 2080's consistent head-to-head victories.