AMD Radeon RX 6600 LE vs AMD Radeon RX 7900M Comparison

# AMD Radeon RX 7900M vs AMD Radeon RX 6600 LE

The AMD Radeon RX 7900M is decisively the stronger GPU in this comparison, leading in every shared benchmark by margins ranging from 87.1% to 119.2%. The RX 7900M posts an average benchmark score of 97,487 versus 70,829 for the RX 6600 LE, a difference of roughly 37.6% in aggregate performance. The RX 7900M also sits at the 94th percentile of all GPUs, while the RX 6600 LE sits at the 91st percentile — a notable gap for two products that both target mobile gaming, but the 7900M clearly operates in a higher performance tier.

FAQ

Q: Which GPU has the higher average benchmark score?

A: The AMD Radeon RX 7900M leads with an average benchmark score of 97,487, compared to 70,829 for the AMD Radeon RX 6600 LE. That is a 37.6% advantage for the 7900M based on the deltaPct between their average scores.

Q: How do the two GPUs compare in Geekbench OpenCL performance?

A: The RX 7900M scores 129,499 in Geekbench OpenCL, while the RX 6600 LE scores 69,229. The RX 7900M wins by 87.1%, a result driven by its substantially higher shading unit count and memory bandwidth.

Q: Which GPU has better Vulkan benchmark performance?

A: The RX 7900M scores 158,760 in Geekbench Vulkan versus 72,428 for the RX 6600 LE. This is the largest relative win for the 7900M in any shared test, with a deltaPct of 119.2%.

Q: What is the process node difference between the two chips?

A: The RX 7900M uses a 5 nm process at TSMC, while the RX 6600 LE uses a 7 nm process at the same foundry. The smaller node contributes to the 7900M’s higher transistor density of 109.1M per mm² versus 46.7M per mm².

Q: Which GPU has more memory and bandwidth?

A: The RX 7900M has 16 GB of GDDR6 on a 256-bit bus, delivering 576.0 GB/s of bandwidth. The RX 6600 LE has 8 GB of GDDR6 on a 128-bit bus, delivering 224.0 GB/s — less than half the bandwidth of the 7900M.

Q: Do both GPUs support the same DirectX and Vulkan versions?

A: Yes, both support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The API feature set is identical even though the underlying architectures differ (RDNA 3.0 vs RDNA 2.0).

Architecture Differences

The RX 7900M is built on the RDNA 3.0 architecture with the Navi 31 chip, codenamed Plum Bonito, while the RX 6600 LE uses the RDNA 2.0 architecture with the Navi 23 chip. This architectural gap is significant: RDNA 3.0 introduces a chiplet-based design that enables the 7900M to pack 57,700 million transistors on a 529 mm² die, compared to 11,060 million transistors on a 237 mm² die for the RX 6600 LE. The transistor density difference is stark — 109.1M per mm² versus 46.7M per mm² — reflecting both the process node shrink from 7 nm to 5 nm and the more advanced design.

The shading unit count is the most dramatic architectural differentiator. The RX 7900M has 4,608 shading units, 288 texture mapping units (TMUs), and 192 render output units (ROPs). The RX 6600 LE has 1,792 shading units, 112 TMUs, and 64 ROPs. That means the 7900M has roughly 2.6 times the shading units, 2.6 times the TMUs, and 3 times the ROPs. Ray tracing hardware follows the same pattern: the 7900M has 72 RT cores versus 28 for the 6600 LE.

Clock behavior also differs. The RX 7900M has a lower base clock of 1825 MHz but a boost clock of 2090 MHz. The RX 6600 LE starts at 1626 MHz base but boosts higher to 2495 MHz, with a game clock of 2045 MHz. Despite the higher boost clock on the 6600 LE, the massive core count advantage of the 7900M overwhelms the clock speed difference in raw throughput.

Memory architecture reinforces the gap. The 7900M uses a 256-bit memory bus with 16 GB of GDDR6 at 18 Gbps effective, yielding 576.0 GB/s. The 6600 LE uses a 128-bit bus with 8 GB at 14 Gbps effective, yielding 224.0 GB/s. The 7900M also draws more power at 180 W TDP versus 132 W, and it is an IGP (integrated graphics package) with no power connectors, while the 6600 LE is a dual-slot card requiring a single 8-pin connector and a 300 W suggested PSU.

Where Each One Wins

The RX 7900M wins in every measurable category from the benchmark data. It dominates in compute workloads, as evidenced by the Geekbench OpenCL result where it scores 129,499 versus 69,229 — an 87.1% lead. This makes it the clear choice for GPU compute tasks such as rendering, scientific simulation, or any OpenCL-accelerated workflow. The Vulkan score of 158,760 versus 72,428 (119.2% lead) further establishes the 7900M as superior for modern graphics APIs, including gaming titles that leverage Vulkan.

The RX 6600 LE has no benchmark wins in this comparison — winsA is 2 and winsB is 0. However, the data suggests it has a role in scenarios where its lower TDP of 132 W and compact dual-slot form factor (190 mm length, 110 mm height, 40 mm width) are preferable. The 6600 LE also has a higher boost clock of 2495 MHz, which could provide competitive single-threaded graphics performance in lighter workloads, though the benchmark data does not show it winning any shared test. For users constrained by power delivery (1x 8-pin vs no connectors) or chassis space, the 6600 LE is the more practical option, but for pure performance, the 7900M wins outright.

Specification Differences

| Specification | AMD Radeon RX 7900M | AMD Radeon RX 6600 LE |

|---|---|---|

| Architecture | RDNA 3.0 | RDNA 2.0 |

| Process Node | 5 nm | 7 nm |

| Transistors | 57,700 million | 11,060 million |

| Die Size | 529 mm² | 237 mm² |

| Transistor Density | 109.1M / mm² | 46.7M / mm² |

| Base Clock | 1825 MHz | 1626 MHz |

| Boost Clock | 2090 MHz | 2495 MHz |

| Game Clock | N/A | 2045 MHz |

| Memory Speed | 2250 MHz (18 Gbps effective) | 1750 MHz (14 Gbps effective) |

| Memory Size | 16 GB | 8 GB |

| Memory Bus Width | 256 bit | 128 bit |

| Memory Bandwidth | 576.0 GB/s | 224.0 GB/s |

| Shading Units | 4608 | 1792 |

| TMUs | 288 | 112 |

| ROPs | 192 | 64 |

| RT Cores | 72 | 28 |

| Pixel Rate | 401.3 GPixel/s | 159.7 GPixel/s |

| Texture Rate | 601.9 GTexel/s | 279.4 GTexel/s |

| FP32 | 38.52 TFLOPS | 8.942 TFLOPS |

| FP16 | 77.05 TFLOPS (2:1) | 17.88 TFLOPS (2:1) |

| TDP | 180 W | 132 W |

| Slot Width | IGP | Dual-slot |

| Power Connectors | None | 1x 8-pin |

| Suggested PSU | N/A | 300 W |

| Bus Interface | PCIe 4.0 x16 | PCIe 4.0 x8 |

| Display Outputs | Portable Device Dependent | 1x HDMI 2.1, 3x DisplayPort 1.4a |

| Dimensions | N/A | 190 mm x 110 mm x 40 mm |

Head-to-Head Benchmarks

The two shared benchmarks tell a consistent story of RX 7900M dominance. In Geekbench OpenCL, the RX 7900M scores 129,499 against the RX 6600 LE’s 69,229, a deltaPct of 87.1%. This translates to the 7900M delivering nearly twice the compute throughput in OpenCL workloads. The FP32 peak rates corroborate this: 38.52 TFLOPS for the 7900M versus 8.942 TFLOPS for the 6600 LE, a 4.3x advantage in theoretical raw compute.

In Geekbench Vulkan, the margin grows even larger. The RX 7900M scores 158,760, while the RX 6600 LE scores 72,428, yielding a 119.2% deltaPct. This result highlights the 7900M’s superior ability to feed its graphics pipeline — the 576.0 GB/s memory bandwidth versus 224.0 GB/s, combined with 288 TMUs versus 112, allows the 7900M to sustain much higher fill rates. The pixel rate difference (401.3 GPixel/s vs 159.7 GPixel/s) and texture rate difference (601.9 GTexel/s vs 279.4 GTexel/s) further explain why the Vulkan gap is so pronounced.

Neither GPU wins a benchmark it does not share — the 6600 LE has no exclusive test, and the 7900M’s 3DMark Steel Nomad DX12 score of 4201 is its only non-Geekbench result, but it has no direct comparison. The average benchmark scores, however, put the 7900M at 97,487 versus 70,829 for the 6600 LE, a 37.6% aggregate lead. The 7900M’s nearest rivals include the AMD Radeon Pro VII (0.4% ahead) and NVIDIA Quadro RTX 6000 (4.3% behind), placing it in workstation-class territory. The 6600 LE, by contrast, sits near the NVIDIA RTX A3000 Mobile (1% ahead) and AMD Radeon RX 6650M (1.3% behind), indicating a mid-range position.

The Verdict

The AMD Radeon RX 7900M is the unequivocal performance winner. It leads the RX 6600 LE in both shared benchmarks by margins of 87.1% and 119.2%, and its average benchmark score of 97,487 is 37.6% higher. The 7900M’s 94th percentile ranking versus the 6600 LE’s 91st percentile confirms that it competes in a higher performance tier, one populated by workstation GPUs like the NVIDIA Quadro RTX 6000 and AMD Radeon Pro VII. For any user prioritizing raw compute, high-resolution gaming, or memory bandwidth, the 7900M is the only choice from this data.

The RX 6600 LE, however, is not without merit. Its 132 W TDP is 48 W lower than the 7900M’s 180 W, and it comes in a compact dual-slot form factor with a 190 mm length, making it easier to integrate into smaller chassis. It also requires only a single 8-pin power connector and a 300 W suggested PSU, whereas the 7900M is an IGP with no discrete power connectors, meaning it relies entirely on the motherboard power delivery. The 6600 LE’s higher boost clock of 2495 MHz also indicates it can reach higher per-core speeds, which may benefit lightly threaded tasks, though no benchmark data confirms this.

For gaming and compute, the RX 7900M delivers more than double the Vulkan performance and nearly double the OpenCL performance. For power-constrained or space-constrained builds, the RX 6600 LE offers a lower power draw and a traditional card form factor. The data is unambiguous: if performance is the sole criterion, the RX 7900M wins by a wide margin; if physical integration and power efficiency are the priorities, the RX 6600 LE is the more practical option. There is no benchmark result in this factor pack where the 6600 LE outperforms the 7900M, so the verdict rests on the 7900M’s decisive lead.