AMD Ryzen 5 PRO 8645HS vs AMD Ryzen 9 8945HS Comparison

The AMD Ryzen 9 8945HS and AMD Ryzen 5 PRO 8645HS are both 8000-series mobile processors built on the same Zen 4 architecture and 4 nm TSMC process, yet they are engineered for distinctly different workloads. The Ryzen 9 8945HS takes the overall benchmark crown with 11 wins across 15 head-to-head tests, but the Ryzen 5 PRO 8645HS counters with a decisive victory in Cinebench R23 multi-core and single-core tests, making it the stronger choice for specific rendering and single-threaded tasks. The data shows a 0.6% difference in average benchmark score (31074 vs 30879), placing both in the 82nd percentile of all CPUs, but their performance profiles diverge sharply depending on the workload type.

FAQ

Q: Which processor has more cores and threads?

A: The AMD Ryzen 9 8945HS has 8 cores and 16 threads, while the AMD Ryzen 5 PRO 8645HS has 6 cores and 12 threads.

Q: How do their base and boost clocks compare?

A: The Ryzen 5 PRO 8645HS has a higher base clock of 4.30 GHz compared to the Ryzen 9 8945HS’s 4.00 GHz, but the Ryzen 9 8945HS boosts higher at 5.20 GHz versus 5.00 GHz for the Ryzen 5 PRO 8645HS.

Q: Which CPU wins in Cinebench R23 multi-core?

A: The AMD Ryzen 5 PRO 8645HS wins by a significant margin, scoring 19742 versus 16795 for the Ryzen 9 8945HS, a 14.9% difference in its favor.

Q: Which chip has better integrated graphics?

A: The Ryzen 9 8945HS features the Radeon 780M, while the Ryzen 5 PRO 8645HS comes with the Radeon 760M.

Q: Do both CPUs support ECC memory?

A: No. The Ryzen 5 PRO 8645HS supports ECC memory, while the Ryzen 9 8945HS does not.

Q: Which socket do they use, and is there a difference?

A: The Ryzen 9 8945HS uses AMD Socket FP8, while the Ryzen 5 PRO 8645HS uses AMD Socket FP7.

Architecture Differences

Both processors share the same fundamental architecture: Zen 4 on the Hawk Point codename, built on TSMC’s 4 nm process with a die size of 178 mm² and 25,000 million transistors. The L1 cache is identical at 64 KB per core, L2 is 1 MB per core, and both have 16 MB of shared L3 cache. Memory support is also the same: DDR5, dual-channel, with 89.6 GB/s bandwidth and PCIe Gen 4 with 20 lanes (CPU only).

The core configurational differences are stark. The Ryzen 9 8945HS offers 8 cores and 16 threads, while the Ryzen 5 PRO 8645HS is cut down to 6 cores and 12 threads. This two-core deficit is the primary driver of multi-threaded performance gaps in most tests. Clock speeds also differ: the Ryzen 9 8945HS has a lower base clock (4.00 GHz) but a higher boost clock (5.20 GHz), while the Ryzen 5 PRO 8645HS starts higher at 4.30 GHz but tops out at 5.00 GHz.

The integrated graphics differ as well, with the Ryzen 9 8945HS carrying the Radeon 780M and the Ryzen 5 PRO 8645HS using the Radeon 760M. The socket is another point of divergence — the Ryzen 9 8945HS uses FP8, whereas the Ryzen 5 PRO 8645HS uses FP7. ECC memory support is exclusive to the Ryzen 5 PRO 8645HS, which could matter for workstation reliability. Both are locked (multiplier not unlocked), both are mobile segment parts, and both are listed as Active in production status.

The Verdict

The AMD Ryzen 9 8945HS is the clear winner for users who need maximum multi-threaded throughput across a broad range of tasks. It wins 11 of 15 head-to-head benchmarks, with dominant margins in integer math (39.2% ahead), floating-point math (35.9% ahead), data compression (34.1% ahead), and Cinebench R15 multi-core (32.7% ahead). Its 8-core/16-thread configuration provides a substantial advantage in parallel workloads, and its higher boost clock of 5.20 GHz helps in bursty single-thread scenarios.

The AMD Ryzen 5 PRO 8645HS is the better pick for specific scenarios where its benchmark wins matter more. It crushes the Ryzen 9 8945HS in Cinebench R23 multi-core by 14.9% (19742 vs 16795) and in single-core by 35.2% (2787 vs 1805). It also edges out the Ryzen 9 8945HS in PassMark single-thread (3858 vs 3850, a 0.2% difference). This makes it the superior choice for applications that favor the R23 workload pattern or for users who prioritize raw single-core performance. Additionally, the Ryzen 5 PRO 8645HS offers ECC memory support, which the Ryzen 9 8945HS lacks.

For most users, the Ryzen 9 8945HS is the safer recommendation given its overwhelming benchmark win count and larger core count. But the Ryzen 5 PRO 8645HS is not merely a budget alternative — in Cinebench R23, it is unequivocally faster, and its ECC support gives it a niche advantage for data-integrity-focused workloads.

Specification Differences

The two CPUs differ in the following specification fields:

• Cores: Ryzen 9 8945HS has 8 cores; Ryzen 5 PRO 8645HS has 6 cores.
• Threads: Ryzen 9 8945HS has 16 threads; Ryzen 5 PRO 8645HS has 12 threads.
• Base Clock: Ryzen 9 8945HS runs at 4.00 GHz; Ryzen 5 PRO 8645HS runs at 4.30 GHz.
• Boost Clock: Ryzen 9 8945HS boosts to 5.20 GHz; Ryzen 5 PRO 8645HS boosts to 5.00 GHz.
• Socket: Ryzen 9 8945HS uses AMD Socket FP8; Ryzen 5 PRO 8645HS uses AMD Socket FP7.
• Integrated Graphics: Ryzen 9 8945HS has Radeon 780M; Ryzen 5 PRO 8645HS has Radeon 760M.
• ECC Memory: Ryzen 9 8945HS does not support ECC; Ryzen 5 PRO 8645HS does support ECC.
• Release Date: Ryzen 9 8945HS released on 2023-12-05; Ryzen 5 PRO 8645HS released on 2024-04-15.
• Part Numbers: Ryzen 9 8945HS has three (100-000001319(FP7r2), 100-000001383(FP7), 100-000001309(FP8)); Ryzen 5 PRO 8645HS has two (100-000001315(FP7r2), 100-000001388(FP7)).

All other specifications — process node, foundry, transistor count, die size, cache hierarchy, memory support, memory bus, memory bandwidth, PCIe lanes, market segment, production status, and unlocked multiplier status — are identical.

Head-to-Head Benchmarks

The benchmark data reveals a clear pattern: the Ryzen 9 8945HS dominates in PassMark workloads, while the Ryzen 5 PRO 8645HS wins decisively in Cinebench R23. The Ryzen 9 8945HS takes 11 wins out of 15 head-to-head tests, but the Ryzen 5 PRO 8645HS’s 4 wins are disproportionately impactful due to their margins.

Starting with the Ryzen 9 8945HS’s biggest victories: it leads by 39.2% in PassMark integer math (101226 vs 72740), by 35.9% in floating-point math (61821 vs 45481), by 34.1% in data compression (356508 vs 265826), and by 32.7% in Cinebench R15 multi-core (2640 vs 1989). It also wins PassMark multi-thread by 26.4% (29780 vs 23569), PassMark extended instructions by 27.1% (26964 vs 21212), and PassMark data encryption by 22.6% (21323 vs 17387). Smaller wins include PassMark find prime numbers (26% ahead, 92 vs 73), PassMark random string sorting (21.8% ahead, 43202 vs 35472), PassMark physics (18.7% ahead, 1434 vs 1208), and Cinebench R15 single-core (0.4% ahead, 281 vs 280).

The Ryzen 5 PRO 8645HS’s wins are concentrated in Cinebench R23. It wins multi-core by 14.9% (19742 vs 16795) and single-core by a massive 35.2% (2787 vs 1805). It also wins both PassMark single-thread and PassMark singlethread tests by 0.2% (3858 vs 3850). The single-core Cinebench R23 gap is the largest margin in either direction across all tests, suggesting a significant architectural or clock-efficiency advantage for the Ryzen 5 PRO 8645HS in that specific workload despite its lower boost clock.

Where Each One Wins

The AMD Ryzen 9 8945HS is the winner for general-purpose multi-threaded computing. Its 8-core/16-thread design delivers consistent advantages in integer math, floating-point math, data compression, encryption, and physics simulations. The 39.2% lead in integer math and 35.9% lead in floating-point math indicate it is substantially better suited for number-crunching applications like financial modeling, scientific computing, and video encoding. Its 34.1% advantage in data compression and 22.6% lead in data encryption also make it the preferred chip for file archiving, database workloads, and security-related processing. The 26.4% lead in PassMark multi-thread reinforces that any parallel workload will run faster on the Ryzen 9 8945HS.

The AMD Ryzen 5 PRO 8645HS wins in scenarios where Cinebench R23 performance is representative of the target application. The 14.9% lead in multi-core and 35.2% lead in single-core are substantial, indicating that this chip excels in rendering tasks that use the R23 benchmark’s specific instruction patterns. The 0.2% win in PassMark single-thread, while marginal, shows that the Ryzen 5 PRO 8645HS is at least on par with the Ryzen 9 8945HS for single-threaded tasks, and in R23 single-core it is far superior. Additionally, the ECC memory support makes the Ryzen 5 PRO 8645HS a more reliable choice for error-sensitive workstation environments where data corruption is unacceptable. Users whose primary applications are Cinebench-like renderers or who require ECC memory should choose the Ryzen 5 PRO 8645HS despite its lower core count.