AMD Ryzen 5 6600H vs AMD Ryzen 7 7840U Comparison

The AMD Ryzen 5 6600H and AMD Ryzen 7 7840U represent two distinct generations of AMD mobile silicon, and the benchmark data presents a remarkably one-sided picture. Across the 17 head-to-head comparisons, the Ryzen 7 7840U wins every single one, leaving the Ryzen 5 6600H with zero victories. This is not a close contest; it is a generational sweep. The Ryzen 7 7840U's dominance is so complete that the analysis shifts from whether it wins to by how much, and what that tells us about the architectural leap between the two.

Where Each One Wins

The data is unambiguous: the AMD Ryzen 7 7840U wins in every measured category. There is no workload, from single-threaded tasks to heavily parallel multi-core operations, where the Ryzen 5 6600H manages to pull ahead. The Ryzen 7 7840U claims all 17 head-to-head benchmarks, including Cinebench R15 and R23, Geekbench, and the full Passmark suite. This means for users prioritizing raw performance, the choice is clear. The Ryzen 5 6600H, with its older Zen 3+ architecture, simply cannot match the newer Zen 4 design in any test. The 7840U’s wins are not marginal either; they range from a minimum of 10.9% in single-threaded tests to a massive 35% in Passmark’s find prime numbers test. The 6600H’s only potential advantage lies in its higher 45W TDP, which might suggest it could sustain performance better in a thick laptop, but the benchmark data does not support this, as it loses even in multi-threaded tests where sustained power would matter most. Conversely, the 7840U achieves these wins while consuming less power, as its TDP is 28W versus 45W for the 6600H, making it the more efficient performer.

Architecture Differences

The fundamental divide between these two processors is the architectural generation. The Ryzen 5 6600H is built on the Zen 3+ architecture, codenamed Rembrandt, and manufactured on a 6nm process at TSMC. The Ryzen 7 7840U, in contrast, uses the newer Zen 4 architecture, codenamed Phoenix, and is produced on a more advanced 4nm process, also at TSMC. This process shrink is significant, allowing for a denser and more power-efficient design. The 7840U packs 25,000 million transistors onto a 178 mm² die, while the 6600H does not have a listed transistor count but has a larger 208 mm² die, suggesting the 4nm process allows for more transistors in a smaller physical space. The core configuration also differs: the 6600H has 6 cores and 12 threads, while the 7840U has 8 cores and 16 threads. This two-core advantage for the 7840U is a primary driver of its multi-threaded performance lead. Cache hierarchies also diverge. Both share a 16 MB L3 cache, but the per-core L2 cache doubles from 512 KB on the 6600H to 1 MB on the 7840U. The L1 cache remains the same at 64 KB per core. Memory bandwidth is another clear point of separation: the 7840U offers 89.6 GB/s versus 76.8 GB/s for the 6600H, despite both supporting dual-channel DDR5. The integrated graphics differ as well, with the 6600H featuring a Radeon 660M and the 7840U featuring the newer Radeon 780M. The 7840U also supports ECC memory, a feature absent on the 6600H. Finally, the sockets are different (FP7 for the 6600H, FP8 for the 7840U), meaning they are not interchangeable in a system.

Head-to-Head Benchmarks

The sheer scale of the 7840U’s victory is best understood by examining the individual benchmark deltas. In Cinebench R23 multi-core, the 7840U scores 12719 against the 6600H’s 10322, a 18.8% difference. This is a substantial gap for a multi-threaded workload, reflecting both the additional two cores and the IPC gains of Zen 4. The single-core story is even more telling. In Geekbench single-core, the 7840U scores 2077 versus 1566 for the 6600H, a 24.6% lead. This is a massive generational improvement, indicating that the 7840U is not just faster when more cores are involved, but it is dramatically faster on a per-thread basis. This single-core advantage is crucial for everyday responsiveness and lightly-threaded applications. The pattern holds across the Passmark suite. In integer math, the 7840U scores 90852 versus 64927, a 28.5% lead. Floating point math shows a 28.9% gap (51767 vs 36796). Even in data encryption, a memory-bandwidth-sensitive task, the 7840U leads by 19.3% (17691 vs 14277). The largest delta is in the find prime numbers test, where the 7840U scores 80 versus 52, a 35% difference, highlighting the raw processing power of the Zen 4 cores. The smallest lead is in the Passmark single-thread test, where the 7840U scores 3565 versus 3178, a 10.9% advantage. This is still a clear win, but it suggests that the single-thread advantage is slightly less pronounced in this specific benchmark compared to Geekbench. In multi-threaded Passmark, the 7840U scores 24782 versus 18669, a 24.7% lead. The data consistently shows a 15-35% performance advantage for the 7840U across all workloads.

FAQ

Q: Which CPU is faster in single-core performance?

A: The AMD Ryzen 7 7840U. In Geekbench single-core, it scores 2077 versus 1566 for the Ryzen 5 6600H, a 24.6% lead. In Cinebench R23 single-core, it scores 1677.5 versus 1458, a 13.1% lead.

Q: Is the Ryzen 7 7840U better for multi-threaded tasks like video editing?

A: Yes, the data confirms this. The 7840U wins all multi-threaded benchmarks. In Cinebench R23 multi-core, it scores 12719 versus 10322 for the 6600H, an 18.8% difference. In Passmark multi-thread, it scores 24782 versus 18669, a 24.7% lead.

Q: What is the TDP difference between the two processors?

A: The Ryzen 5 6600H has a TDP of 45W, while the Ryzen 7 7840U has a TDP of 28W. This is a significant difference, making the 7840U more power-efficient despite being faster.

Q: Do these processors have the same amount of cache?

A: They share the same 16 MB of L3 cache, but they differ in L2 cache. The Ryzen 5 6600H has 512 KB of L2 per core, while the Ryzen 7 7840U has 1 MB per core.

Q: Which CPU has a higher boost clock?

A: The Ryzen 7 7840U has a higher boost clock of 5.10 GHz, compared to the 4.50 GHz of the Ryzen 5 6600H. Their base clocks are identical at 3.30 GHz.

Q: Are these CPUs compatible with the same motherboard socket?

A: No. The Ryzen 5 6600H uses AMD Socket FP7, while the Ryzen 7 7840U uses AMD Socket FP8.

The Verdict

The benchmark data is unequivocal: the AMD Ryzen 7 7840U is the superior processor in every measurable way. For any user prioritizing performance, from gaming to content creation to heavy multitasking, the 7840U is the clear choice. Its 24.6% lead in Geekbench single-core and 18.8% lead in Cinebench R23 multi-core are not minor advantages; they represent a full generational leap in capability. The 7840U achieves this while also having a lower TDP of 28W versus 45W, making it a more efficient option for thin-and-light laptops. The Ryzen 5 6600H, while not a poor performer in absolute terms (it holds a 78th percentile vs all CPUs), is simply outclassed by its newer sibling. The only conceivable reason to choose the 6600H would be if a specific laptop model with it is significantly cheaper, but based purely on performance data, there is no workload where it wins. The 7840U’s 77th percentile ranking is slightly lower than the 6600H’s 78th, but this is an artifact of the 7840U competing in a higher performance tier; in direct head-to-head comparisons, it wins 100% of the time. The verdict is simple: if you have the option, the Ryzen 7 7840U is the definitive choice.

Specification Differences

The following table outlines the key specifications where the two processors differ.

| Specification | AMD Ryzen 5 6600H | AMD Ryzen 7 7840U |

| :--- | :--- | :--- |

| Series | 6000 series | 7000 series |

| Cores | 6 | 8 |

| Threads | 12 | 16 |

| Boost Clock | 4.50 GHz | 5.10 GHz |

| TDP | 45W | 28W |

| Socket | AMD Socket FP7 | AMD Socket FP8 |

| Architecture | Zen 3+ | Zen 4 |

| Codename | Rembrandt | Phoenix |

| Process Node | 6 nm | 4 nm |

| Transistors | Not listed | 25,000 million |

| Die Size | 208 mm² | 178 mm² |

| L2 Cache | 512 KB (per core) | 1 MB (per core) |

| Memory Bandwidth | 76.8 GB/s | 89.6 GB/s |

| ECC Memory | No | Yes |

| Integrated Graphics | Radeon 660M | Radeon 780M |

| Part Number | 100-000000546100-000000562 | 100-000000829100-000000830100-000001131 |