AMD Ryzen AI Embedded P164i vs AMD Ryzen Embedded 8645HS Comparison

The AMD Ryzen AI Embedded P164i and the AMD Ryzen Embedded 8645HS are both mobile-class embedded processors from AMD, sharing the same Socket FP8 and the same 4 nm TSMC process node. However, their design philosophies diverge sharply: the P164i is a hybrid-core part with higher core count and a newer architecture generation, while the 8645HS is a homogeneous Zen 4 design with higher base clocks and more PCIe lanes. The recorded database shows no direct head-to-head benchmark scores, no average benchmark scores, and no nearest rival deltas for either processor, so the analysis below relies strictly on the specification differences and architectural data available.

Head-to-Head Benchmarks

The database contains no direct benchmark results for either processor in the head-to-head comparison table. Both entries list an average benchmark score of 0 and a percentile rank of 50 relative to all CPUs. Consequently, there are no exact numbers to compare for multi-core throughput, single-core speed, or integrated graphics performance. The absence of recorded measurements means that any statement about relative performance must be inferred from the physical and architectural specifications, not from actual benchmark outcomes.

That said, the specification sheet offers several quantitative differences that will likely translate into measurable benchmark gaps. The P164i has 8 cores and 16 threads, while the 8645HS has 6 cores and 12 threads. In heavily threaded workloads, the P164i’s two extra cores and four extra threads provide a structural advantage. The P164i’s boost clock is 5.00 GHz, identical to the 8645HS’s boost clock of 5.00 GHz, so the peak single-thread frequency does not differ. However, the base clocks are very different: the P164i runs at 2.00 GHz, while the 8645HS runs at 4.30 GHz. That 2.30 GHz base clock gap means the 8645HS will sustain higher frequencies under continuous load, especially in scenarios where the P164i’s lower-power hybrid design might throttle earlier.

The L3 cache also differs substantially. The 8645HS has 16 MB of shared L3 cache, exactly double the 8 MB L3 cache of the P164i. For workloads that are cache-sensitive, such as database lookups, compression, or certain scientific computations, the 8645HS may show better latency behavior. The P164i, conversely, has a larger L1 cache per core at 80 KB versus 64 KB on the 8645HS, which can help with per-core working sets. The L2 cache is identical at 1 MB per core for both.

Integrated graphics differ as well. The P164i uses the Radeon 880M, while the 8645HS uses the Radeon 760M. Without benchmark scores, the relative graphics performance is not quantified, but the model number hierarchy suggests the 880M is a higher-tier part. The memory support also differs: the P164i supports both DDR5 and LPDDR5X, while the 8645HS supports DDR5 only. Both have dual-channel memory buses and identical memory bandwidth ratings of 89.6 GB/s, so the bandwidth ceiling is the same, but the P164i’s LPDDR5X option may allow lower power consumption in compact systems.

The PCIe configuration is a clear point of difference. The P164i provides Gen 4 with 16 lanes (CPU only), while the 8645HS provides Gen 4 with 20 lanes (CPU only). The 8645HS offers four additional PCIe lanes, which matters for embedded systems that need to attach multiple peripherals, storage devices, or expansion cards. For a dense I/O application, the 8645HS has the structural edge.

Where Each One Wins

Based on the recorded specifications, the P164i wins in scenarios that favor higher core counts, newer architecture generation, and flexible memory options. Its 8 cores and 16 threads make it the better choice for parallel workloads such as virtualization with many small virtual machines, containerized microservices, or software-based packet processing. The Zen 5 / Zen 5c hybrid architecture, as labeled in the generation field, suggests a mix of high-performance and high-efficiency cores, which can be beneficial for workloads that have varied thread intensity. The support for LPDDR5X memory gives system designers the option to use lower-power memory, which is useful in thermally constrained embedded environments. The P164i also has a larger per-core L1 cache, which may help in latency-sensitive single-thread tasks within a multi-threaded context.

The 8645HS wins in scenarios that depend on sustained all-core frequency, raw cache capacity, and PCIe expansion. Its 4.30 GHz base clock is more than double the P164i’s 2.00 GHz base clock, meaning that for workloads that are not heavily threaded but require consistent high frequency, the 8645HS will likely sustain better performance. The 16 MB of L3 cache is double the P164i’s 8 MB, giving it an advantage in applications that repeatedly access a moderate-sized dataset. The 20 PCIe lanes, compared to 16 on the P164i, make the 8645HS more suitable for systems that need to connect high-speed NVMe drives, network interface cards, or FPGA accelerators without a separate PCIe switch. The 8645HS also has a larger die at 178 mm² versus 233 mm² for the P164i, which is a smaller physical footprint, though the P164i’s larger die may accommodate the additional cores and newer architecture.

The TDP difference is notable: the P164i is rated at 28 watts, while the 8645HS is rated at 45 watts. This means the P164i will draw less power under load, making it the better fit for fanless or battery-powered embedded systems, whereas the 8645HS requires more robust thermal management but offers higher sustained frequency.

FAQ

Q: Which processor has more cores and threads?

A: The AMD Ryzen AI Embedded P164i has 8 cores and 16 threads, while the AMD Ryzen Embedded 8645HS has 6 cores and 12 threads.

Q: Do the two processors have the same boost clock?

A: Yes, both the P164i and the 8645HS have a boost clock of 5.00 GHz. Their base clocks differ: 2.00 GHz for the P164i and 4.30 GHz for the 8645HS.

Q: Which processor has more L3 cache?

A: The AMD Ryzen Embedded 8645HS has 16 MB of shared L3 cache, while the AMD Ryzen AI Embedded P164i has 8 MB of L3 cache.

Q: What are the PCIe lane counts for each processor?

A: The P164i provides 16 PCIe Gen 4 lanes (CPU only), and the 8645HS provides 20 PCIe Gen 4 lanes (CPU only).

Q: Which processor supports LPDDR5X memory?

A: Only the AMD Ryzen AI Embedded P164i supports LPDDR5X memory, in addition to DDR5. The 8645HS supports DDR5 only.

Q: What is the TDP difference between the two?

A: The P164i has a TDP of 28 watts, and the 8645HS has a TDP of 45 watts.

Q: Which processor has a newer architecture generation?

A: The P164i is listed under the generation “Ryzen AI Embedded (Zen 5 / Zen 5c)”, while the 8645HS is listed under “Ryzen Embedded (Zen 4 (Hawk Point))”. The P164i therefore uses a newer generation.

Specification Differences

The two processors differ in several core specification fields. The P164i has 8 cores and 16 threads, versus 6 cores and 12 threads on the 8645HS. The base clock is 2.00 GHz on the P164i and 4.30 GHz on the 8645HS, while the boost clock is identical at 5.00 GHz. The TDP is 28 watts for the P164i and 45 watts for the 8645HS. Both use AMD Socket FP8.

The cache hierarchy differs in L1 and L3. The P164i has 80 KB of L1 cache per core and 8 MB of L3 cache, while the 8645HS has 64 KB of L1 cache per core and 16 MB of shared L3 cache. Both have 1 MB of L2 cache per core.

Memory support differs: the P164i supports DDR5 and LPDDR5X, while the 8645HS supports DDR5 only. Both have dual-channel memory buses and the same memory bandwidth of 89.6 GB/s. Both support ECC memory.

PCIe configuration differs: the P164i has Gen 4 with 16 lanes (CPU only), and the 8645HS has Gen 4 with 20 lanes (CPU only).

Integrated graphics differ: the P164i uses the Radeon 880M, and the 8645HS uses the Radeon 760M.

The die size differs: 233 mm² for the P164i and 178 mm² for the 8645HS. The 8645HS has a transistor count of 25,000 million, while the P164i has no recorded transistor count. The release dates differ: the P164i was released on 2026-03-08, and the 8645HS was released on 2024-04-01. The 8645HS belongs to the 8000 series, while the P164i has no series listing. Neither processor has an unlocked multiplier.

Architecture Differences

The P164i is built on the Gorgon Point codename with a generation label of “Ryzen AI Embedded (Zen 5 / Zen 5c)”. This indicates a hybrid architecture that combines Zen 5 and Zen 5c cores, which typically means a mix of full-performance cores and compact high-density cores. The 8645HS uses the Hawk Point codename with the architecture explicitly listed as Zen 4. The 8645HS is homogeneous, using only Zen 4 cores.

Both processors are fabricated on a 4 nm process at TSMC, but the die sizes differ: 233 mm² for the P164i and 178 mm² for the 8645HS. The larger die on the P164i likely accommodates the extra cores and the hybrid core design. The transistor count is only recorded for the 8645HS, at 25,000 million, which is a high density for a 178 mm² die.

The cache architecture reflects the core design. The P164i uses 80 KB of L1 per core, which is larger than the 64 KB per core on the 8645HS. The L3 cache is smaller on the P164i at 8 MB, compared to 16 MB on the 8645HS. The L2 cache is the same size per core at 1 MB.

The integrated graphics differ: the P164i includes the Radeon 880M, while the 8645HS includes the Radeon 760M. The P164i’s memory controller supports LPDDR5X, which is not available on the 8645HS. The PCIe controller on the 8645HS offers more lanes, 20 versus 16.

The release date gap is significant: the 8645HS launched in April 2024, while the P164i launched in March 2026, roughly two years later. The newer generation on the P164i reflects that time gap.

The Verdict

The data indicates that the AMD Ryzen AI Embedded P164i is the processor to choose for multi-threaded, power-constrained embedded applications. Its 8 cores and 16 threads, paired with a 28-watt TDP, make it suitable for systems that must process many concurrent tasks while managing heat and energy budgets. The support for LPDDR5X memory adds flexibility for compact designs that use low-power memory. The newer Zen 5 / Zen 5c architecture and the larger L1 cache per core suggest an updated microarchitecture that may deliver better instructions per clock on certain workloads, though no benchmark scores exist to confirm this.

The AMD Ryzen Embedded 8645HS is the processor to choose for I/O-heavy, frequency-sensitive embedded systems. Its 4.30 GHz base clock is far higher than the P164i’s 2.00 GHz, which will help in workloads that do not scale perfectly with core count and instead rely on sustained single-thread or lightly threaded performance. The 16 MB L3 cache doubles the P164i’s cache capacity, which can reduce memory latencies for data-intensive operations. The 20 PCIe lanes provide more headroom for peripheral connectivity, and the 45-watt TDP, while higher, reflects an ability to maintain higher frequencies under load.

Neither processor has recorded benchmark scores or rival comparisons in the database, so the verdict rests entirely on specification analysis. For a system that prioritizes core count, efficiency, and newer architecture, the P164i is the clear pick. For a system that prioritizes base frequency, cache size, and PCIe bandwidth, the 8645HS is the clear pick. The identical boost clock of 5.00 GHz means peak single-thread speed is the same, but the 8645HS will reach and hold high frequencies more readily given its higher base clock. The P164i’s lower TDP and LPDDR5X support make it more suitable for passively cooled or battery-powered devices, while the 8645HS demands active cooling but delivers more consistent high-frequency performance. The choice between the two is a choice between a modern efficiency-oriented hybrid design and a proven, high-frequency homogeneous design with more I/O capability.