AMD Radeon RX 6600M vs NVIDIA GeForce RTX 3080 Comparison

FAQ

Q: Which GPU wins more benchmark tests overall?

A: The NVIDIA GeForce RTX 3080 wins 9 out of 10 head-to-head benchmarks, while the AMD Radeon RX 6600M wins only 1. The sole AMD victory comes in Geekbench Vulkan, where it scores 73740 versus NVIDIA's 33620, a 119.3% advantage.

Q: How do the two cards compare in average benchmark score?

A: Despite the lopsided win count, their average benchmark scores are nearly identical. The AMD Radeon RX 6600M averages 23273, while the NVIDIA GeForce RTX 3080 averages 23172. Both sit at the 68th percentile among all GPUs.

Q: What is the biggest single-benchmark margin between them?

A: The largest gap is in 3DMark Steel Nomad DX12, where the RTX 3080 scores 4407 versus the RX 6600M's 1495. That represents a 66.1% deficit for the AMD card — the second-largest margin is in Geekbench OpenCL, where NVIDIA leads 152423 to 67765, a 55.5% gap.

Q: Are these cards direct competitors based on performance tier?

A: The nearestRivals data shows they are extremely close in aggregate performance. The RX 6600M's closest rival is the AMD Radeon R9 M290X at 23276 (0% delta), and the RTX 3080's closest rival includes the RX 6600M itself at 23273 (-0.4% delta). They are effectively peer products in average score.

Q: Which card has higher raw compute throughput?

A: The RTX 3080 delivers 29.77 TFLOPS FP32, more than triple the RX 6600M's 8.659 TFLOPS. The NVIDIA card also achieves 29.77 TFLOPS FP16 (1:1 ratio), while the AMD card offers 17.32 TFLOPS FP16 (2:1 ratio).

Q: How do memory subsystems differ between the two?

A: The RTX 3080 uses 10 GB of GDDR6X on a 320-bit bus with 760.3 GB/s bandwidth. The RX 6600M has 8 GB of GDDR6 on a 128-bit bus with 224.0 GB/s bandwidth. The NVIDIA card's memory bandwidth is over three times higher.

The Verdict

The data presents a clear split between gaming performance and compute workloads. If the priority is DirectX 12 gaming, the NVIDIA GeForce RTX 3080 is the definitive choice — it wins 3DMark Steel Nomad DX12 by 66.1% and Passmark DX12 by 48%. The RTX 3080 also dominates compute tasks, leading Passmark GPU Compute by 60.8% and Geekbench OpenCL by 55.5%.

However, the AMD Radeon RX 6600M has one notable strength: Vulkan performance. Its 119.3% advantage in Geekbench Vulkan is the largest single win in the entire comparison. For applications that leverage Vulkan, the RX 6600M is decisively ahead.

The average benchmark scores tell a different story than the head-to-head results. With the RX 6600M at 23273 and the RTX 3080 at 23172, the aggregate performance is nearly indistinguishable — a 0.4% difference in favor of AMD. This suggests that the RTX 3080's wins are concentrated in specific tests, while the RX 6600M's Vulkan outlier compensates heavily in the average.

For buyers prioritizing modern DirectX 12 gaming and compute-heavy workloads, the RTX 3080 is the stronger pick based on the benchmark data. For Vulkan-centric applications, the RX 6600M is unexpectedly superior. The RTX 3080 also carries a launch MSRP of 699 USD, which can be stated as a point of reference. Given the RTX 3080's 9-to-1 win ratio and massive margins in most tests, the data favors NVIDIA for general-purpose use.

Head-to-Head Benchmarks

The RTX 3080's dominance is most pronounced in 3DMark Steel Nomad DX12, where it scores 4407 against the RX 6600M's 1495 — a 66.1% advantage. This is the single largest margin in the entire comparison and highlights NVIDIA's strength in modern DirectX 12 rendering workloads.

Geekbench OpenCL shows a similar pattern, with the RTX 3080 posting 152423 versus 67765 for the RX 6600M, a 55.5% lead. This aligns with the compute-oriented design of the Ampere architecture, which delivers 29.77 TFLOPS FP32 compared to the RDNA 2 card's 8.659 TFLOPS.

Passmark GPU Compute reinforces the compute gap: 14397 for NVIDIA versus 5646 for AMD, a 60.8% deficit. The RTX 3080 also wins Passmark G3D with 25086 against 13929, a 44.5% margin, and Passmark DirectX 10 with 170 versus 87 (48.8% gap).

The RTX 3080 wins every Passmark DirectX test. In DirectX 11, it scores 207 versus 136 (34.3% ahead). In DirectX 9, it posts 258 versus 184 (28.7% ahead). In DirectX 12, it doubles the AMD card: 100 versus 52 (48% gap). Even in 2D performance, Passmark G2D shows NVIDIA ahead at 1054 versus 728, a 30.9% margin.

The RX 6600M's lone victory is remarkable in its magnitude. In Geekbench Vulkan, the AMD card scores 73740, more than double the RTX 3080's 33620. The 119.3% delta means the RX 6600M is over 2.1 times faster in this specific workload. This is an outlier result that suggests AMD's RDNA 2 architecture has a significant Vulkan optimization advantage.

Notably, the RTX 3080 does not have a Geekbench Metal score listed, while the RX 6600M posts 92237 in that test. This absence limits direct comparison on Apple's Metal API, but the available data shows NVIDIA's strength across the remaining tests.

Specification Differences

The two cards differ substantially in nearly every hardware specification. The RTX 3080 uses the GA102 chip on an 8 nm Samsung process, while the RX 6600M uses the Navi 23 chip on a 7 nm TSMC process. The RTX 3080 packs 28,300 million transistors on a 628 mm² die, versus 11,060 million transistors on 237 mm² for the RX 6600M. Transistor density is similar: 45.1M per mm² for NVIDIA and 46.7M per mm² for AMD.

Memory configurations diverge sharply. The RTX 3080 offers 10 GB of GDDR6X on a 320-bit bus with 760.3 GB/s bandwidth, while the RX 6600M has 8 GB of GDDR6 on a 128-bit bus with 224.0 GB/s bandwidth. The NVIDIA card's memory clock runs at 1188 MHz (19 Gbps effective), compared to 1750 MHz (14 Gbps effective) for AMD.

Compute resources heavily favor NVIDIA. The RTX 3080 has 8704 shading units, 272 TMUs, 96 ROPs, 68 RT cores, and 272 tensor cores. The RX 6600M has 1792 shading units, 112 TMUs, 64 ROPs, and 28 RT cores, with no tensor cores listed. Pixel rate is similar — 164.2 GPixel/s for NVIDIA versus 154.6 GPixel/s for AMD — but texture rate favors NVIDIA at 465.1 GTexel/s versus 270.6 GTexel/s.

Clock speeds and power draw tell opposite stories. The RX 6600M boosts to 2416 MHz with a 100 W TDP, while the RTX 3080 boosts to 1710 MHz with a 320 W TDP. Physical design differs: the RTX 3080 is a dual-slot card measuring 285 mm in length, 112 mm in height, and 40 mm in width, requiring a 700 W suggested PSU and a 1x 12-pin power connector. The RX 6600M is an IGP with no power connectors and portable-device-dependent display outputs.

Architecture Differences

The architectural divide is fundamental. AMD uses RDNA 2.0, while NVIDIA employs Ampere. Both support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, but their implementations differ radically.

The RTX 3080's Ampere architecture integrates 272 tensor cores alongside 68 RT cores, enabling dedicated AI acceleration and hardware ray tracing. The RX 6600M has 28 RT cores but no tensor cores, meaning it lacks NVIDIA's tensor-core-based features entirely. This explains the RTX 3080's FP16 performance: it achieves 29.77 TFLOPS at a 1:1 ratio with FP32, while the RX 6600M's FP16 runs at a 2:1 ratio, delivering 17.32 TFLOPS from 8.659 TFLOPS FP32.

Transistor counts reflect architectural complexity. The RTX 3080's 28,300 million transistors on a 628 mm² die enable 8704 shading units, while the RX 6600M's 11,060 million transistors on 237 mm² support only 1792. The die-size difference is massive — 628 mm² versus 237 mm² — yet transistor density is nearly identical, indicating both use similarly dense manufacturing.

The process nodes differ: TSMC's 7 nm for AMD versus Samsung's 8 nm for NVIDIA. This gives AMD a slight process advantage, but NVIDIA compensates with a much larger die and higher power budget. The RX 6600M's 100 W TDP targets mobile integration, while the RTX 3080's 320 W TDP suits desktop dual-slot designs.

The RTX 3080 uses a PCIe 4.0 x16 interface, while the RX 6600M uses PCIe 4.0 x8. NVIDIA's wider bus offers more bandwidth for data transfer between GPU and system. Display outputs differ: the RTX 3080 provides 1x HDMI 2.1 and 3x DisplayPort 1.4a, while the RX 6600M's outputs are portable-device dependent.

Generation lineage also differs. The RX 6600M belongs to the Navi Mobile (RX 6000M) generation with a predecessor of Polaris Mobile, while the RTX 3080 is from GeForce 30, succeeding GeForce 20 and preceding GeForce 40. Both are end-of-life products, with the RTX 3080 releasing on 2020-08-31 and the RX 6600M on 2021-05-30.