AMD Radeon RX 6600S vs AMD Radeon RX 7600M XT Comparison

Head-to-Head Benchmarks

The head-to-head results show a decisive overall victory for the AMD Radeon RX 7600M XT, which takes 6 of the 8 benchmark comparisons. The most significant gap appears in PassMark GPU Compute, where the RX 7600M XT scores 7140 against 4879 for the RX 6600S, a 46.3% advantage. This is the largest delta in the entire comparison and highlights a major difference in raw compute throughput.

The second largest win for the RX 7600M XT comes in PassMark DirectX 11, where it scores 137 versus 105, a 30.5% advantage. This is a notable result for legacy API gaming workloads. The PassMark G2D test also favors the RX 7600M XT heavily, with a score of 894 compared to 647, representing a 38.2% lead in 2D graphics performance.

In the more modern gaming API test, PassMark DirectX 12, the RX 7600M XT wins by a narrower margin, 58 to 56, a 3.6% difference. The 3DMark Steel Nomad DX12 test was only recorded for the RX 7600M XT, with a score of 2048; no comparable data exists for the RX 6600S. Similarly, Geekbench Vulkan results are only available for the RX 760M XT at 27793. The Geekbench OpenCL test shows the RX 7600M XT scoring 74869 against 66435, a 12.7% lead.

The RX 6600S does claim two wins. Its PassMark DirectX10 score of 81 beats the RX 7600M XT's 76, which is a 6.2% advantage for the older card. It also edges out the RX 7600M XT in PassMark DirectX9, scoring 176 to 175, a marginal 0.6% difference.

When looking at overall averages, the RX 7600M XT has an average benchmark score of 12710, placing it in the 52nd percentile of all GPUs. This puts it directly between the NVIDIA GeForce GTX 670 (12773, 0.5% ahead) and the NVIDIA Tesla K20Xm (12625, 0.7% behind). The RX 6600S has an average score of 10629, sitting in the 49th percentile, and its nearest rival is the AMD Radeon R9 M275X (10582, 0.4% behind). The gap in average score between the two chips is 2081 points, which is roughly 19.6% of the RX 6600S's score, a substantial margin.

Architecture Differences

The architectural differences between these two mobile GPUs are significant, spanning process technology, core configuration, and memory subsystems. The RX 7600M XT is built on the RDNA 3.0 architecture, using the Navi 33 chip, while the RX 6600S is based on the older RDNA 2.0 architecture with the Navi 23 chip.

The manufacturing process is a critical differentiator. The RX 7600M XT uses TSMC's 6 nm process node, while the RX 6600S uses TSMC's 7 nm node. This reflects a generational refinement in manufacturing density. The RX 7600M XT packs 13,300 million transistors onto a 204 mm² die, resulting in a density of 65.2 million transistors per square millimeter. The RX 6600S fits 11,060 million transistors on a larger 237 mm² die, achieving a lower 46.7 million transistors per square millimeter. This means the RX 7600M XT packs about 20.3% more transistors into a 13.9% smaller die area.

The core configurations differ significantly. The RX 760M XT has 2048 shading units, 128 texture mapping units, and 64 raster operations pipelines. The RX 6600S has fewer shading units at 1792, fewer TMUs at 112, but the same 64 ROPs. The ray tracing core counts also differ, with the RX 7600M XT featuring 32 RT cores versus 28 on the RX 6600S.

Clock speeds tell an interesting story. The RX 6600S has a higher base clock at 1700 MHz, but the RX 7600M XT has a higher boost clock at 2469 MHz. The RX 7600M XT also has a higher game clock at 2023 MHz compared to the 1881 MHz of the RX 6600S. This boost clock advantage is substantial, at 23.5% higher.

The memory subsystem is a clear area of divergence. The RX 7600M XT comes with 8 GB of GDDR6 memory, while the RX 6600S has only 4 GB of GDDR6. Both use a 128-bit bus width, but the memory clock differs significantly. The RX 7600M XT operates at 2250 MHz (18 Gbps effective), yielding 288.0 GB/s of bandwidth. The RX 6600S runs at 1750 MHz (14 Gbps effective), providing 224.0 GB/s. This gives the RX 7600M XT a 28.6% bandwidth advantage.

The resulting fill rates and compute throughput reflect these differences. The RX 7600M XT achieves a pixel rate of 158.0 GPixel/s and texture rate of 316.0 GTexel/s. The RX 6600S achieves 128.0 GPixel/s and 224.0 GTexel/s. Floating point performance is a major gap: the RX 7600M XT delivers 20.23 TFLOPS FP32, while the RX 6600S delivers 7.168 TFLOPS FP32, a 182.6% advantage. The power envelopes also differ, with the RX 7600M XT rated at 120 W TDP versus 80 W for the RX 6600S.

Where Each One Wins

The data indicates distinct use cases for each GPU. The RX 7600M XT is the clear winner for compute-intensive tasks. Its 46.3% lead in the GPU Compute benchmark is the strongest single result in the comparison. This, combined with its significantly higher FP32 throughput, makes it the better choice for workloads that leverage general-purpose GPU computing, such as rendering, simulation, or machine learning inference. Its 12.7% lead in Geekbench OpenCL reinforces this position.

For gaming, the RX 7600M XT dominates the DirectX 11 and DirectX 12 results. The 30.5% lead in DirectX 11 is particularly large, suggesting a strong advantage in older games. The 3.6% lead in DirectX 12 is more modest, but it is still a win. The lack of a 3DMark Steel Nomad result for the RX 6600S means the modern gaming comparison is incomplete, but the DirectX 12 result suggests the RX 7600M XT holds the edge in modern titles.

The RX 6600S has wins in only two tests: DirectX 9 and DirectX 10. The DirectX 9 margin is negligible at 0.6%, but the DirectX 10 win of 6.2% is more substantial. This suggests that the RX 6600S might have a slight edge in very old legacy applications or games from the early 2000s era. However, these are narrow margins and the scores are low absolute numbers, making them less impactful for modern workloads.

The RX 7600M XT also wins in 2D workloads, scoring 38.2% higher in the G2D test. This could matter for desktop composition, video playback, and other non-3D tasks. The RX 6600S does not have any recorded win in a modern compute or graphics test.

FAQ

Q: Which GPU has the higher boost clock?

A: The AMD Radeon RX 7600M XT has a higher boost clock at 2469 MHz, while the AMD Radeon RX 6600S has a boost clock of 2000 MHz.

Q: How do they compare in memory bandwidth?

A: The RX 7600M XT has 288.0 GB/s of bandwidth, which is 28.6% higher than the 224.0 GB/s of the RX 6600S. This is due to the faster memory speed of 18 Gbps versus 14 Gbps.

Q: What is the difference in the number of shading units?

A: The RX 7600M XT has 2048 shading units, while the RX 6600S has 1792 shading units, a difference of 256 units.

Q: Does the RX 6600S have any benchmark wins?

A: Yes, the RX 6600S wins in two legacy DirectX tests: PassMark DirectX 10 (81 vs 76) and PassMark DirectX 9 (176 vs 175).

Q: What is the average benchmark score for each?

A: The RX 7600M XT has an average benchmark score of 12710, while the RX 6600S has an average score of 10629. The RX 7600M XT also holds a higher percentile rank, 52 vs 49.

Q: How do the total transistor counts compare?

A: The RX 7600M XT contains 13,300 million transistors, while the RX 6600S contains 11,060 million transistors.

The Verdict

Based strictly on the recorded benchmark data, the AMD Radeon RX 7600M XT is the superior GPU. It wins 6 out of 8 direct comparisons, including all tests for modern graphics APIs and compute workloads. Its 46.3% lead in GPU Compute and 30.5% lead in DirectX 11 are decisive. Its average benchmark score of 12710 is significantly higher than the RX 6600S's 10629, and its 52nd percentile rank is above the RX 6600S's 49th.

The RX 7600M XT is the recommended choice for users looking for higher performance in gaming and compute tasks. Its larger memory capacity of 8 GB, higher bandwidth, and 2.8x higher FP32 throughput provide a clear performance headroom over the RX 6600S.

The RX 6600S, however, offers a much lower power envelope at 80 W TDP compared to 120 W. This could make it a more suitable option for thin-and-light laptops where thermal and power constraints are critical. It is also the only one of the two with wins in DirectX 10 and DirectX 9, though these are narrow margins. However, for any task that requires modern graphics or significant compute, the data overwhelmingly points to the RX 7600M XT. The RX 6600S also has a much lower transistor count and is on an older architecture, which is reflected in its lower benchmark scores.