AMD Ryzen 5 7540U vs AMD Ryzen 5 PRO 6650H Comparison

The AMD Ryzen 5 PRO 6650H and AMD Ryzen 5 7540U are both six-core, 12-thread mobile processors, but the benchmark data reveals they are not equals. The 7540U wins 14 of 17 head-to-head tests, often by substantial double-digit margins, while the 6650H manages only three victories. Despite this lopsided result, both CPUs sit at the 76th percentile among all CPUs, and their average benchmark scores are remarkably close: 24,364 for the 6650H versus 24,188 for the 7540U, a difference of just 0.7%. This paradox—one chip dominating individual tests yet tying in the aggregate—suggests the two are optimized for different workloads, making the choice between them less about overall performance and more about specific use cases.

The Verdict

The data points to a clear split: the Ryzen 5 7540U is the superior choice for general computing, single-threaded tasks, and most multi-threaded workloads. It leads in every Cinebench and Geekbench test, with its single-core advantage ranging from 10.6% in Cinebench R15 to 16.7% in Geekbench. For users whose primary tasks involve productivity applications, web browsing, or any software that relies on strong per-core performance, the 7540U is the data-backed pick. Its 4.90 GHz boost clock versus the 6650H's 4.50 GHz helps explain this edge, as does its newer Zen 4 architecture.

The Ryzen 5 PRO 6650H, however, is not obsolete. It wins in data compression (2.9% ahead), data encryption (7.6% ahead), and integer math (4.5% ahead). These are specific, compute-heavy workloads where the older chip's design apparently excels. For anyone running encryption-heavy tasks or integer-based calculations, the 6650H offers a measurable, if modest, performance advantage. The verdict is not "which is better" but "which is better for what": the 7540U for general speed, the 6650H for niche math and security workloads.

Where Each One Wins

The 7540U's dominance is most pronounced in single-threaded and lightly-threaded benchmarks. Its largest victory is in Geekbench single-core, where it scores 2,083 versus 1,735, a 16.7% margin. PassMark single-thread shows a 12.2% lead (3,544 vs. 3,110), and Cinebench R23 single-core is 13.4% ahead (1,699 vs. 1,471). These results indicate a significant per-core efficiency gain from the newer architecture. The 7540U also wins in multi-threaded tests like Geekbench multi-core (7,956 vs. 6,930, a 12.9% lead) and Cinebench R23 multi-core (10,383 vs. 9,561, a 7.9% lead), showing that its advantages scale beyond single-thread performance. Physics calculations also favor it heavily, with a 13.1% lead (964 vs. 838).

The 6650H's three wins are in PassMark data compression (217,700 vs. 211,581), data encryption (13,518 vs. 12,563), and integer math (62,838 vs. 60,152). These are not trivial tasks; encryption and integer math are foundational to many server and scientific workloads. The 6650H's 7.6% encryption lead is its best result and suggests a specialized advantage. Interestingly, the 7540U does not sweep all math tests—it wins floating-point math by just 0.9% (36,077 vs. 35,743) and extended instructions by 1.7% (15,307 vs. 15,044), but loses integer math. This pattern hints that the 6650H's older Zen 3+ architecture may have a more efficient integer execution pipeline, even if its overall clock speed is lower.

Architecture Differences

The two chips represent distinct architectural generations. The 6650H is based on Zen 3+ with the codename Rembrandt, built on a 6 nm process at TSMC with a die size of 208 mm². The 7540U uses Zen 4 with the codename Phoenix, built on a 4 nm process, also at TSMC, with a smaller die at 178 mm² and 25,000 million transistors. This process shrink is a key factor in the 7540U's performance-per-watt advantage, though the 6650H's higher 45W TDP versus the 7540U's 28W TDP suggests it is designed for thicker, more power-hungry laptops.

Cache configurations differ significantly. Both have 64 KB of L1 and 16 MB of shared L3, but the 7540U doubles the L2 cache to 1 MB per core versus 512 KB per core on the 6650H. This larger L2 cache likely contributes to the 7540U's single-threaded superiority, as more data can be stored closer to the cores. Memory support is identical in type (DDR5, dual-channel), but the 7540U has higher bandwidth at 89.6 GB/s versus 76.8 GB/s. A notable feature difference: the 7540U supports ECC memory, while the 6650H does not. Both use the same AMD Socket FP7 and offer PCIe Gen 4 with 20 lanes. The integrated graphics differ, with the 6650H featuring a Radeon 660M and the 7540U a Radeon 740M. The 7540U is also newer, released on 2023-05-02 versus 2022-04-18 for the 6650H.

FAQ

Q: Which CPU has a higher boost clock?

A: The AMD Ryzen 5 7540U has a boost clock of 4.90 GHz, while the AMD Ryzen 5 PRO 6650H boosts to 4.50 GHz.

Q: Does the Ryzen 5 7540U support ECC memory?

A: Yes, the 7540U supports ECC memory, whereas the 6650H does not. This makes the 7540U more suitable for error-sensitive workloads.

Q: Which processor is better for single-threaded performance?

A: The data clearly shows the 7540U is superior, with a 16.7% lead in Geekbench single-core (2,083 vs. 1,735), a 13.4% lead in Cinebench R23 single-core (1,699 vs. 1,471), and a 12.2% lead in PassMark single-thread (3,544 vs. 3,110).

Q: In what areas does the Ryzen 5 PRO 6650H outperform the 7540U?

A: The 6650H wins in PassMark data compression (217,700 vs. 211,581), data encryption (13,518 vs. 12,563), and integer math (62,838 vs. 60,152), with margins of 2.9%, 7.6%, and 4.5% respectively.

Q: Are the core and thread counts the same?

A: Yes, both processors have 6 cores and 12 threads. They also share the same 16 MB of shared L3 cache, but the 7540U has 1 MB of L2 per core versus 512 KB on the 6650H.

Q: How do their average benchmark scores compare?

A: The 6650H has an average benchmark score of 24,364, and the 7540U scores 24,188, meaning the 6650H is 0.7% ahead in aggregate despite losing most individual tests. Both rank in the 76th percentile of all CPUs.

Head-to-Head Benchmarks

The biggest win for the 7540U is in Geekbench single-core, where it scores 2,083 against the 6650H's 1,735, a 16.7% advantage. This is followed by PassMark find prime numbers, where the 7540U's 66 points beat 52, a 21.2% margin—the largest percentage difference in any test. Geekbench multi-core also heavily favors the 7540U: 7,956 versus 6,930, a 12.9% lead. Cinebench R23 single-core shows a 13.4% gap (1,699 vs. 1,471), and PassMark physics is 13.1% better (964 vs. 838). Cinebench R15 single-core is 10.6% higher (264 vs. 236), and PassMark single-thread is 12.2% higher (3,544 vs. 3,110). Multi-threaded Cinebench R23 shows a 7.9% edge (10,383 vs. 9,561), while Cinebench R15 multi-core is 7.5% better (1,676 vs. 1,550). PassMark random string sorting is 7.8% better (24,760 vs. 22,823), and PassMark multithread is 3.4% ahead (18,576 vs. 17,936). The 7540U also narrowly wins extended instructions by 1.7% (15,307 vs. 15,044) and floating-point math by 0.9% (36,077 vs. 35,743).

The 6650H's wins are smaller but notable. Its best is data encryption at 13,518 versus 12,563, a 7.6% margin. Integer math sees it ahead 62,838 to 60,152, a 4.5% difference. Data compression is its narrowest win: 217,700 versus 211,581, a 2.9% edge. These three victories demonstrate that the 6650H is not uniformly slower, but its strengths are concentrated in specific algorithmic areas.

Specification Differences

The two processors differ in several key specifications beyond their benchmark scores. The 6650H has a base clock of 3.30 GHz and a boost clock of 4.50 GHz, while the 7540U runs at 3.20 GHz base and 4.90 GHz boost. The 6650H has a TDP of 45W, significantly higher than the 7540U's 28W. The architecture differs: Zen 3+ (Rembrandt) for the 6650H versus Zen 4 (Phoenix) for the 7540U. The process node is 6 nm for the 6650H and 4 nm for the 7540U, with die sizes of 208 mm² and 178 mm² respectively. The 7540U lists 25,000 million transistors; the 6650H's transistor count is not listed. L2 cache is 512 KB per core on the 6650H versus 1 MB per core on the 7540U, while L1 and L3 are identical at 64 KB per core and 16 MB shared. Memory bandwidth favors the 7540U at 89.6 GB/s versus 76.8 GB/s. ECC memory support is present only on the 7540U. The integrated graphics differ: Radeon 660M on the 6650H, Radeon 740M on the 7540U. Both share the same socket (AMD Socket FP7), PCIe configuration (Gen 4, 20 lanes), and memory type (DDR5, dual-channel). Release dates are 2022-04-18 for the 6650H and 2023-05-02 for the 7540U.