AMD EPYC 4565P vs AMD Ryzen 9 PRO 9945 Comparison

The AMD Ryzen 9 PRO 9945 and AMD EPYC 4565P are two Zen 5 processors aimed at the server and workstation market, both utilizing the AMD Socket AM5 platform. While they share a 4nm process node and identical transistor counts, their benchmark results reveal distinct performance profiles. The data shows a clear split: the EPYC 4565P dominates in heavily threaded and data-intensive workloads, while the Ryzen 9 PRO 9945 carves out a narrow but decisive lead in a specific computational task.

Where Each One Wins

The benchmark results indicate that the AMD EPYC 4565P is the outright performance leader in nearly every measured category. Out of the 11 head-to-head comparisons, the EPYC 4565P wins 10, with margins ranging from a slim 2% to a substantial 36.9%. Its victories are concentrated in workloads that scale with core count and memory throughput, such as data compression, encryption, and floating-point math. For instance, in the passmark_data_compression test, the EPYC 4565P scores 860,786 against the Ryzen 9 PRO 9945's 579,972, a difference of 32.6%. This pattern holds across integer math, multithreaded performance, and random string sorting, where the EPYC's additional cores provide a significant advantage.

The AMD Ryzen 9 PRO 9945, despite having fewer cores, secures a single win in the passmark_find_prime_numbers test. Its score of 342 compared to the EPYC 4565P's 294 represents a 16.3% advantage. This result is notable because it suggests the Ryzen 9 PRO 9945 has a specific architectural or clock-speed edge that benefits this particular algorithmic workload, which is often sensitive to single-thread efficiency and cache latency rather than raw core count. Outside of this anomaly, the Ryzen 9 PRO 9945 trails in all other benchmarks, including single-thread performance, where it scores 4,619 versus the EPYC's 4,712, a 2% deficit.

The use-case split is therefore stark. The EPYC 4565P is the choice for general-purpose server workloads, database operations, and any task that can utilize its 16 cores and 32 threads. The Ryzen 9 PRO 9945, with its 12 cores and 24 threads, appears more specialized, offering a surprising edge in prime-number calculations, which might translate to advantages in certain types of scientific or cryptographic computations that rely on this operation.

Architecture Differences

Both processors are built on the same fundamental architecture, but they are configured differently. The Ryzen 9 PRO 9945 is part of the 9000 series with the codename "Granite Ridge," while the EPYC 4565P belongs to the EPYC 4005 series with the codename "Grado." Both use the Zen 5 microarchitecture and are fabricated on a 4nm process by TSMC, with a die size of 2x 70.6 mm² and 16,630 million transistors.

The primary architectural difference is the core configuration. The EPYC 4565P features 16 cores and 32 threads, while the Ryzen 9 PRO 9945 has 12 cores and 24 threads. This core count disparity directly explains the EPYC's dominance in multithreaded benchmarks. Furthermore, the EPYC 4565P has a higher base clock of 4.30 GHz and a boost clock of 5.70 GHz, compared to the Ryzen 9 PRO 9945's 3.40 GHz base and 5.40 GHz boost. This clock advantage is reflected in the EPYC's higher scores in both single-thread and multi-thread tests.

Cache configurations are also identical in capacity but differ in description. Both have 80 KB of L1 cache per core and 1 MB of L2 cache per core. The L3 cache is 64 MB in both cases, though the FACT PACK describes the Ryzen 9 PRO 9945's as "64 MB" and the EPYC 4565P's as "64 MB (shared)." This distinction suggests the EPYC's L3 is explicitly shared across all cores, which is a common design for server processors to reduce data access latency. Both support dual-channel DDR5 memory with a bandwidth of 89.6 GB/s and have ECC memory support. They also both feature 24 PCIe Gen 5 lanes and integrated Radeon Graphics.

The most significant non-performance difference is the TDP. The Ryzen 9 PRO 9945 has a TDP of 65 watts, while the EPYC 4565P has a TDP of 170 watts. This 105-watt difference indicates that the EPYC is designed for sustained high-performance operation, likely requiring more robust cooling solutions, whereas the Ryzen 9 PRO 9945 is more power-efficient and easier to cool. The release dates also differ, with the EPYC 4565P launching on 2025-05-12 and the Ryzen 9 PRO 9945 launching later on 2025-09-15.

Head-to-Head Benchmarks

The data shows the EPYC 4565P's largest wins come in data-intensive tasks. In passmark_data_encryption, the EPYC scores 48,268 against the Ryzen's 30,450, a 36.9% advantage. This is the largest delta in the set. Similarly, in passmark_data_compression, the EPYC's 860,786 versus the Ryzen's 579,972 represents a 32.6% lead. These are the kinds of workloads where having 16 cores versus 12 cores provides a tangible scaling benefit.

In raw compute tasks, the EPYC also leads decisively. The passmark_integer_math score is 250,683 for the EPYC versus 171,175 for the Ryzen, a 31.7% difference. Floating-point math shows a 29.4% gap, with scores of 152,003 and 107,340 respectively. The multithread score is 63,474 for the EPYC against 48,664 for the Ryzen, a 23.3% difference. Extended instructions also favor the EPYC by 31%, with scores of 64,345 versus 44,374.

The margins shrink considerably in single-threaded and physics-based tests. In passmark_single_thread, the EPYC scores 4,712 versus the Ryzen's 4,619, a mere 2% difference. The passmark_physics test shows a similarly narrow margin, with the EPYC at 2,976 and the Ryzen at 2,902, a 2.5% difference. These results indicate that while the EPYC has a clock speed advantage, the per-core performance of both chips is very close.

The single exception to the EPYC's dominance is passmark_find_prime_numbers. Here, the Ryzen 9 PRO 9945 scores 342, which is 16.3% higher than the EPYC's 294. This is a surprising result given the EPYC's higher clock speeds. The data suggests that the Ryzen 9 PRO 9945's memory hierarchy or a specific scheduling advantage allows it to excel in this particular algorithmic pattern, which is often bottlenecked by cache access times rather than raw arithmetic throughput.

The Verdict

From the data, the AMD EPYC 4565P is the superior processor for almost all server and workstation tasks. Its 16 cores and 32 threads, combined with higher clock speeds, produce wins in 10 of 11 benchmarks, including the most common general-purpose workloads. The EPYC's 23.3% lead in multithreaded performance and 36.9% lead in data encryption make it the clear choice for database servers, virtualization hosts, and content creation workstations that can leverage parallel processing. Its higher TDP of 170 watts is the trade-off for this performance, but for a server socket, that is a reasonable expectation.

The AMD Ryzen 9 PRO 9945 is not without merit, but its case is narrower. Its 65-watt TDP makes it a far more energy-efficient option, which could be critical for dense deployments where power and cooling are at a premium. Its single win in prime-number finding, with a 16.3% advantage, suggests it might be preferred for specialized workloads that heavily rely on that specific operation. However, its 2% deficit in single-thread performance and 23.3% deficit in multithread performance mean it is not a general-purpose replacement for the EPYC. The Ryzen 9 PRO 9945 is best suited for scenarios where power efficiency is paramount and the workload aligns with its unique strength.

FAQ

Q: Which processor has a higher core count?

A: The AMD EPYC 4565P has 16 cores and 32 threads, while the AMD Ryzen 9 PRO 9945 has 12 cores and 24 threads.

Q: How much faster is the EPYC 4565P in multithreaded performance?

A: The EPYC 4565P scores 63,474 in the passmark_multithread test, which is 23.3% higher than the Ryzen 9 PRO 9945's score of 48,664.

Q: In which benchmark does the Ryzen 9 PRO 9945 beat the EPYC 4565P?

A: The Ryzen 9 PRO 9945 wins the passmark_find_prime_numbers test with a score of 342, which is 16.3% higher than the EPYC 4565P's score of 294.

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

A: The Ryzen 9 PRO 9945 has a TDP of 65 watts, while the EPYC 4565P has a TDP of 170 watts.

Q: Do both processors support ECC memory and DDR5?

A: Yes, both the Ryzen 9 PRO 9945 and the EPYC 4565P support DDR5 memory and have ECC memory support enabled.

Q: What is the performance margin in single-thread tests?

A: The EPYC 4565P scores 4,712 in the passmark_single_thread test, which is 2% higher than the Ryzen 9 PRO 9945's score of 4,619.

Specification Differences

| Specification | AMD Ryzen 9 PRO 9945 | AMD EPYC 4565P |

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

| Series | 9000 series | EPYC 4005 series |

| Codename | Granite Ridge | Grado |

| Generation | Ryzen 9 (Zen 5 (Granite Ridge)) | EPYC (Zen 5 (Grado)) |

| Cores | 12 | 16 |

| Threads | 24 | 32 |

| Base Clock | 3.40 GHz | 4.30 GHz |

| Boost Clock | 5.40 GHz | 5.70 GHz |

| TDP | 65 W | 170 W |

| L3 Cache | 64 MB | 64 MB (shared) |

| Release Date | 2025-09-15 | 2025-05-12 |

| Part Number | 100-000001407 | 100-000001559 |