AMD EPYC 9755 vs AMD EPYC 9965 Comparison

The AMD EPYC 9965 and AMD EPYC 9755 are both flagship server processors built on the Zen 5 architecture, yet they are engineered for fundamentally different workloads. The 9965 is a dense, core-heavy part, while the 9755 is a higher-clocked, cache-rich alternative. Benchmark data shows a clear performance split: the 9965 wins 6 of 17 head-to-head tests, while the 9755 takes the remaining 11. This is not a simple victory lap for either; instead, it is a study in how core count, clock speed, and cache size dictate workload suitability.

Where Each One Wins

The AMD EPYC 9965 is the champion of data throughput. It dominates in tests that stress memory bandwidth and parallel data manipulation. In PassMark’s data compression test, the 9965 scores 5,427,555, which is 20.1% higher than the 9755’s 4,517,407. Similarly, it leads in floating-point math with a score of 1,141,430 versus 922,900, a 23.7% advantage, and in integer math with a 16.5% lead (1,806,439 vs. 1,549,946). The 9965 also wins in extended instructions (29.3% ahead) and random string sorting (6.8% ahead), while taking a solid 11.1% lead in data encryption. This pattern points to a processor that excels when the task is moving and transforming large volumes of data, where its 192 cores and 384 threads can be kept busy by the memory subsystem.

The AMD EPYC 9755, conversely, wins on responsiveness and single-threaded efficiency. It is the pick for latency-sensitive and lightly threaded tasks. The 9755 wins every Cinebench test, from R15 to R23, in both single and multi-core variants, by a consistent 3.3%. Its PassMark single-thread score of 3,503 is 8.4% higher than the 9965’s 3,210. The most dramatic difference is in physics calculations, where the 9755 scores 27,806, a massive 28.9% ahead of the 9965’s 19,782. It also wins the prime number search test with 2,047 points, a 39% improvement over the 9965. The 9755’s higher base clock of 2.70 GHz and boost clock of 4.10 GHz give it a decisive edge in tasks that cannot be parallelized efficiently, making it the better choice for simulation, gaming servers, or any workload where a single core’s speed is the bottleneck.

Architecture Differences

The two processors share the same Zen 5 architecture and AMD Socket SP5, but they are distinct physical implementations. The 9965 is built on the 3nm process node from TSMC, while the 9755 uses a 4nm node. This process difference is a key reason for the 9965’s core count advantage. The 9965 packs 192 cores and 384 threads, while the 9755 offers a still-massive 128 cores and 256 threads. Both have a TDP of 500 watts.

Cache configuration is another major divergence. The 9965 has an L3 cache of 384 MB shared, whereas the 9755 has a much larger 512 MB shared L3 cache. Both parts have 80 KB of L1 cache and 1 MB of L2 cache per core. The larger L3 on the 9755 is likely a contributing factor to its higher single-thread scores, as more data can be held closer to the core. The 9755 also has a documented transistor count of 133,040 million and a die size of 16x 70.6 mm², though no equivalent figures are listed for the 9965.

Both processors support DDR5 memory over a twelve-channel bus, providing 576.0 GB/s of bandwidth, and they feature Gen 5 PCIe with 128 lanes (CPU only). They also both support ECC memory. The 9755’s generation is listed as "EPYC (Zen 5 (Turin))", while the 9965 is listed as "EPYC (Zen 5c (Turin))". This "5c" designation signals a denser, more compact core layout, which explains why the 9965 can deliver 192 cores on a smaller process node. The 9755, with its full-size Zen 5 cores, achieves higher clock speeds but fewer total cores.

Head-to-Head Benchmarks

The most striking trend in the head-to-head data is the 9755’s universal 3.3% lead across all six Cinebench tests. This includes R15, R20, and R23, in both single and multi-core modes. For example, in Cinebench R23 multi-core, the 9755 scores 141,378 against the 9965’s 136,661. In single-core, the 9755 posts 19,959 versus 19,293. This consistency suggests a fundamental clock speed advantage that applies to both single and multi-threaded rendering workloads.

The 9965’s wins are in PassMark’s specialized workloads. The largest margin is in extended instructions, where the 9965 scores 392,159, a 29.3% advantage over the 9755’s 303,321. This test often measures AVX-512 style workloads, and the 9965’s sheer core count overwhelms the 9755’s clock speed advantage. In floating-point math, the 9965 wins 1,141,430 to 922,900, a 23.7% margin. Integer math shows a 16.5% lead for the 9965. Data compression is a 20.1% win for the 9965. These are all highly parallel workloads where 192 cores can be fully utilized.

The 9755’s wins outside of Cinebench are in PassMark’s physics engine and prime number finding. The physics test is a 28.9% landslide for the 9755 (27,806 vs. 19,782), and the prime number test is a 39% blowout (2,047 vs. 1,249). These tests are notoriously sensitive to single-thread performance and clock speed. The PassMark multithread score, however, is close: the 9755 wins with 166,328 versus 160,778, a 3.3% margin. This indicates that in a general multi-threaded mix, the 9755’s higher clocks compensate for its 33% fewer cores.

FAQ

Q: Which processor has more cores?

A: The AMD EPYC 9965 has 192 cores and 384 threads, while the AMD EPYC 9755 has 128 cores and 256 threads.

Q: Is the 9965 always faster in multi-threaded tasks?

A: No. While the 9965 wins in specific data-heavy PassMark tests, the 9755 wins every Cinebench multi-core test by 3.3%, as well as the PassMark multithread score.

Q: Which CPU offers better single-threaded performance?

A: The AMD EPYC 9755 is clearly superior. It wins all single-core Cinebench tests by 3.3% and the PassMark single-thread test by 8.4%.

Q: Do they use the same memory architecture?

A: Yes, both support DDR5 memory over a twelve-channel bus with 576.0 GB/s bandwidth and ECC support.

Q: What is the difference in their L3 cache sizes?

A: The 9965 has 384 MB of shared L3 cache, while the 9755 has a larger 512 MB of shared L3 cache.

Q: Which processor has a higher boost clock?

A: The AMD EPYC 9755 has a boost clock of 4.10 GHz, compared to the 9965’s 3.70 GHz.

Specification Differences

| Specification | AMD EPYC 9965 | AMD EPYC 9755 |

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

| Cores | 192 | 128 |

| Threads | 384 | 256 |

| Base Clock | 2.25 GHz | 2.70 GHz |

| Boost Clock | 3.70 GHz | 4.10 GHz |

| Process Node | 3 nm (TSMC) | 4 nm (TSMC) |

| L3 Cache | 384 MB (shared) | 512 MB (shared) |

| Transistors | Not listed | 133,040 million |

| Die Size | Not listed | 16x 70.6 mm² |

| Generation | EPYC (Zen 5c (Turin)) | EPYC (Zen 5 (Turin)) |

| Launch MSRP | $14813 | $12984 |

The two parts share identical TDP (500W), socket (SP5), memory support (DDR5, twelve-channel, 576.0 GB/s), PCIe (Gen 5, 128 lanes), and release date (2024-10-09). The 9755 is the faster and cheaper part per the listed launch MSRP, but the 9965 offers 50% more cores for a 14% higher price. The data suggests that the 9965 is for throughput-bound workloads, while the 9755 is for latency-bound ones.