AMD Ryzen 5 6600U vs AMD Ryzen 5 PRO 8540U Comparison

The Verdict

The AMD Ryzen 5 PRO 8540U and AMD Ryzen 5 6600U are both six-core, twelve-thread mobile processors, but they target different priorities. The benchmark database shows the PRO 8540U wins 12 of 15 head-to-head comparisons, with its most dramatic advantage coming in sustained multi-threaded workloads. The Ryzen 5 6600U holds a narrower edge in a few specific tasks, notably integer math and Cinebench R15 single-core. The data indicates the PRO 8540U is the pick for users who need maximum throughput in rendering, physics simulation, or data compression. The 6600U remains a sensible choice for workloads that favor its particular strengths, especially legacy single-threaded tests, though its overall average benchmark score of 22897 trails the PRO 8540U's 23709. Both chips sit in the 76th percentile of all CPUs in the database, meaning either will deliver above-average mobile performance, but the PRO 8540U consistently pulls ahead in the tasks that matter most for productivity.

Architecture Differences

The two processors come from different AMD generations and use distinct silicon. The Ryzen 5 PRO 8540U is built on Zen 4 architecture with the Hawk Point codename, part of the 8000 series. It is manufactured on a 4 nm process at TSMC, with a die size of 137 mm² and 20,900 million transistors. In contrast, the Ryzen 5 6600U uses Zen 3+ architecture under the Rembrandt codename, belonging to the 6000 series. It is produced on a 6 nm process at the same foundry, with a notably larger die size of 208 mm²; the database does not list a transistor count for this part. The newer process node gives the PRO 8540U a fundamental density advantage, though both chips share the same L1 cache configuration of 64 KB per core and a shared L3 cache of 16 MB. The L2 cache differs: the PRO 8540U has 1 MB per core, while the 6600U has 512 KB per core. Both support DDR5 memory on a dual-channel bus, but the PRO 8540U offers higher memory bandwidth at 89.6 GB/s versus 76.8 GB/s for the 6600U. The PRO 8540U also adds ECC memory support, a feature absent on the 6600U. PCIe lanes differ as well: the 6600U provides Gen 4 with 20 lanes (CPU only), while the PRO 8540U offers Gen 4 with 14 lanes. Integrated graphics also differ, with the PRO 8540U featuring a Radeon 740M and the 6600U a Radeon 660M. Both use AMD Socket FP7 and are active production parts with locked multipliers.

Head-to-Head Benchmarks

The most striking result in the database is Cinebench R23 multi-core, where the PRO 8540U scores 15456 against 9159.5 for the 6600U, a 68.7% advantage. This massive gap reflects both the newer architecture and the higher 28 W TDP of the PRO 8540U versus the 15 W TDP of the 6600U. Single-core Cinebench R23 also favors the PRO 8540U, with a score of 2182 versus 1456.5, a 49.8% lead. In Cinebench R15 multi-core, the PRO 8540U wins more modestly at 1557 against 1493, a 4.3% edge. Interestingly, the 6600U takes Cinebench R15 single-core with a score of 233 versus 219, a 6% advantage, though that test is not present in the head-to-head list.

PassMark results paint a mixed but generally positive picture for the PRO 8540U. In data compression, it scores 205703 versus 201364, a 2.2% win. Extended instructions favor the PRO 8540U at 15410 versus 13356, a 15.4% margin. Find prime numbers shows a 29.4% lead for the PRO 8540U (66 versus 51). Floating point math is close: 34865 versus 33991, a 2.6% win for the PRO 8540U. Multithreaded performance in PassMark gives the PRO 8540U a 7% edge (18218 versus 17026). Physics simulation shows a 19.2% advantage (983 versus 825). Random string sorting favors the PRO 8540U by 16.7% (24797 versus 21241). Single-thread PassMark scores put the PRO 8540U at 3563 versus 3132, a 13.8% lead.

The 6600U claims three wins. Integer math is its best result: 61723 versus 56738, an 8.1% advantage for the older chip. Data encryption also goes to the 6600U at 12783 versus 12319, a 3.6% margin. The third win is the already noted Cinebench R15 single-core, though the database records it as a -6% delta for the PRO 8540U. These wins show the 6600U retains some computational strengths, particularly in integer-heavy and encryption workloads, despite losing the broader architectural battle.

Specification Differences

The database records several specification gaps between the two processors. The PRO 8540U has a base clock of 3.20 GHz and a boost clock of 4.90 GHz, while the 6600U runs at 2.90 GHz base and 4.50 GHz boost. TDP is a major differentiator: 28 W for the PRO 8540U versus 15 W for the 6600U. The process node shifts from 6 nm for the 6600U to 4 nm for the PRO 8540U. Die size differs sharply: 137 mm² for the PRO 8540U versus 208 mm² for the 6600U. The PRO 8540U lists 20,900 million transistors, while the 6600U has no recorded transistor count. L2 cache per core is 1 MB on the PRO 8540U versus 512 KB on the 6600U. Memory bandwidth is 89.6 GB/s for the PRO 8540U versus 76.8 GB/s for the 6600U. ECC memory support is present only on the PRO 8540U. PCIe lane count favors the 6600U at 20 lanes versus 14 lanes for the PRO 8540U. Integrated graphics are Radeon 740M on the PRO 8540U versus Radeon 660M on the 6600U. The PRO 8540U has a recorded release date of April 15, 2024, while the 6600U has no release date in the database. Both chips share the same socket, core count, thread count, L1 cache, L3 cache, memory type (DDR5), memory bus (dual-channel), and market segment (mobile). Neither has an unlocked multiplier. Neither has a recorded launch MSRP.

FAQ

Q: Which processor has a higher multi-core Cinebench R23 score?

A: The AMD Ryzen 5 PRO 8540U scores 15456 in Cinebench R23 multi-core, which is 68.7% higher than the AMD Ryzen 5 6600U's score of 9159.5.

Q: Are there any benchmarks where the AMD Ryzen 5 6600U wins?

A: Yes, the 6600U wins three head-to-head tests: PassMark integer math (61723 versus 56738, an 8.1% advantage), PassMark data encryption (12783 versus 12319, a 3.6% margin), and Cinebench R15 single-core (233 versus 219, a 6% lead).

Q: How do the power ratings compare?

A: The Ryzen 5 PRO 8540U has a TDP of 28 W, while the Ryzen 5 6600U has a TDP of 15 W. This higher power envelope contributes to the PRO 8540U's performance advantages.

Q: Do both processors support ECC memory?

A: No, only the AMD Ryzen 5 PRO 8540U supports ECC memory. The AMD Ryzen 5 6600U does not list ECC support in the database.

Q: What is the memory bandwidth difference?

A: The PRO 8540U provides 89.6 GB/s of memory bandwidth, while the 6600U provides 76.8 GB/s. Both use DDR5 on a dual-channel bus.

Q: Which chip has a smaller manufacturing process?

A: The Ryzen 5 PRO 8540U is built on a 4 nm process, while the Ryzen 5 6600U uses a 6 nm process. The PRO 8540U also has a smaller die size at 137 mm² compared to 208 mm² for the 6600U.