AMD EPYC 9555P vs Intel Xeon 6781P Comparison

The Intel Xeon 6781P and AMD EPYC 9555P are both flagship server processors, but benchmark results show they excel in distinctly different types of workloads. The AMD EPYC 9555P wins the majority of head-to-head tests, claiming 10 of 14 comparisons, while the Intel Xeon 6781P counters with 4 decisive victories in specialized tasks. Both chips sit in the 99th percentile of all CPUs, yet their average benchmark scores diverge: the Intel Xeon 6781P posts an average of 315,524, which is 1.2% ahead of the AMD EPYC 9575F and 1.6% ahead of the AMD EPYC 9734, while the EPYC 9555P’s average of 287,066 trails the Intel Xeon 696X by 0.3% and the AMD EPYC 9565 by 0.6%.

Head-to-Head Benchmarks

The AMD EPYC 9555P establishes its dominance in Cinebench multi-core rendering tests, where it outperforms the Intel Xeon 6781P by a consistent 13% margin across all three versions. In Cinebench R15 multi-core, the EPYC 9555P scores 11,610 against Intel’s 10,105; in R20 it posts 48,378 versus 42,106; and in R23 it reaches 115,186 against 100,254. This uniformity suggests a fundamental throughput advantage in heavily threaded, floating-point-heavy workloads rather than a test-specific anomaly.

The gap widens further in integer math, where the EPYC 9555P’s 787,106 score crushes the Intel Xeon 6781P’s 584,834 — a 25.7% difference that represents the largest single delta in the entire benchmark suite. Data encryption also favors AMD decisively, with the EPYC 9555P scoring 148,896 against Intel’s 119,623, a 19.7% advantage. The EPYC 9555P additionally leads in data compression (2,639,400 vs 2,441,690, a 7.5% edge), multi-thread performance (123,576 vs 117,946, 4.6% ahead), random string sorting (280,398 vs 268,573, 4.2% ahead), and single-thread performance (3,410 vs 3,152, 7.6% ahead).

The Intel Xeon 6781P fights back in prime number finding with a stunning 58.1% advantage — scoring 1,687 versus AMD’s 1,067 — a result that points to a specific algorithmic strength in integer-heavy, latency-sensitive operations. Intel also wins in physics calculations, posting 17,753 against AMD’s 15,474, a 14.7% margin. Floating-point math goes to Intel by a narrower 4.3% (507,406 vs 486,407), and extended instructions favor Intel by 4.2% (199,048 vs 191,082). These wins suggest that while AMD dominates aggregate throughput, Intel retains an edge in certain specialized instruction paths and physics simulation workloads.

FAQ

Q: Which processor has more cores and threads?

A: The Intel Xeon 6781P has 80 cores and 160 threads, while the AMD EPYC 9555P has 64 cores and 128 threads. Despite having 25% fewer cores, the EPYC 9555P wins the majority of benchmark comparisons, indicating higher per-core efficiency.

Q: How do the two chips compare in single-threaded performance?

A: The AMD EPYC 9555P scores 3,410 in PassMark single-thread tests versus the Intel Xeon 6781P’s 3,152, giving AMD a 7.6% advantage. This aligns with the EPYC 9555P’s higher base clock of 3.20 GHz and boost clock of 4.40 GHz, compared to Intel’s 2.00 GHz base and 3.80 GHz boost.

Q: Which processor wins in data encryption workloads?

A: The AMD EPYC 9555P is significantly faster, scoring 148,896 in PassMark data encryption versus Intel’s 119,623 — a 19.7% advantage. This is one of the largest performance gaps between the two processors.

Q: Where does the Intel Xeon 6781P have its biggest advantage?

A: The Intel Xeon 6781P’s largest win is in PassMark find prime numbers, where it scores 1,687 against AMD’s 1,067 — a 58.1% difference. It also leads in physics (14.7%), floating-point math (4.3%), and extended instructions (4.2%).

Q: What is the cumulative benchmark score difference?

A: The Intel Xeon 6781P has an average benchmark score of 315,524, while the AMD EPYC 9555P averages 287,066. This places Intel 1.2% ahead of the AMD EPYC 9575F and 1.6% ahead of the AMD EPYC 9734, while AMD’s score is 0.3% behind the Intel Xeon 696X.

Q: Do both processors support ECC memory and PCIe Gen 5?

A: Yes, both support ECC memory and PCIe Gen 5. The Intel Xeon 6781P offers 136 lanes (CPU only), while the AMD EPYC 9555P provides 128 lanes (CPU only). Both use DDR5 memory, though AMD’s bus is twelve-channel versus Intel’s eight-channel.

Architecture Differences

The two processors represent fundamentally different design philosophies. The Intel Xeon 6781P uses the Granite Rapids architecture, fabricated on Intel’s 5 nm process, with a die size of 2x 598 mm². The AMD EPYC 9555P employs the Zen 5 architecture under the Turin codename, built on TSMC’s 4 nm process with a die size of 8x 70.6 mm² and 66,520 million transistors. The process node difference — 4 nm versus 5 nm — likely contributes to AMD’s superior clock speeds despite a higher 360 W TDP versus Intel’s 350 W.

Cache hierarchies diverge substantially. The Intel Xeon 6781P allocates 112 KB of L1 cache per core, 2 MB of L2 per core, and a massive 336 MB of shared L3 cache. The AMD EPYC 9555P uses 80 KB L1 per core, 1 MB L2 per core, and 256 MB of shared L3. Intel’s larger L3 cache — 80 MB more — may explain its wins in physics and prime number tests, where large working sets benefit from on-die storage. AMD’s smaller per-core caches but higher clock speeds point to a design optimized for raw throughput rather than cache capacity.

Memory architectures also differ. The EPYC 9555P features a twelve-channel memory bus delivering 576.0 GB/s bandwidth, while the Xeon 6781P uses eight channels at 409.6 GB/s. AMD’s 40% bandwidth advantage likely underpins its wins in data compression and encryption, which are memory-intensive. Both support DDR5 and ECC, but AMD’s wider bus gives it a structural edge in bandwidth-bound scenarios.

The socket platforms are incompatible: Intel uses Socket 4710, while AMD uses Socket SP5. Both are active production processors with no integrated graphics, and neither has an unlocked multiplier. The Intel Xeon 6781P was released on 2025-02-23, while the EPYC 9555P launched earlier on 2024-10-09, part of the EPYC 9005 series.

Specification Differences

| Specification | Intel Xeon 6781P | AMD EPYC 9555P |

|---|---|---|

| Cores | 80 | 64 |

| Threads | 160 | 128 |

| Base Clock | 2.00 GHz | 3.20 GHz |

| Boost Clock | 3.80 GHz | 4.40 GHz |

| TDP | 350 W | 360 W |

| Process Node | 5 nm (Intel) | 4 nm (TSMC) |

| Die Size | 2x 598 mm² | 8x 70.6 mm² |

| Transistors | Not listed | 66,520 million |

| L1 Cache | 112 KB (per core) | 80 KB (per core) |

| L2 Cache | 2 MB (per core) | 1 MB (per core) |

| L3 Cache | 336 MB (shared) | 256 MB (shared) |

| Memory Bus | Eight-channel | Twelve-channel |

| Memory Bandwidth | 409.6 GB/s | 576.0 GB/s |

| PCIe Lanes | 136 (Gen 5) | 128 (Gen 5) |

| Socket | Intel Socket 4710 | AMD Socket SP5 |

| Launch Date | 2025-02-23 | 2024-10-09 |

| Part Number | SRV5J | 100-000001523 |

The specifications reveal a clear trade-off: Intel offers 25% more cores and 80 MB more L3 cache, while AMD counters with 60% higher base clock, 15.8% higher boost clock, 50% wider memory bus, and 40.6% more memory bandwidth. The EPYC 9555P also uses a more advanced 4 nm process with a dramatically smaller total die area (565.6 mm² versus 1,196 mm²), suggesting better power efficiency per unit of silicon.

The Verdict

The data paints a clear picture for workload-specific recommendations. The AMD EPYC 9555P is the better choice for general-purpose server workloads, database operations, and data-intensive tasks. Its wins span Cinebench rendering (13% across all versions), data encryption (19.7%), integer math (25.7%), and single-thread performance (7.6%). The twelve-channel memory bus delivering 576.0 GB/s provides a structural advantage that shows up across memory-bound benchmarks. For enterprises running mixed virtualized workloads, high-frequency trading, or data analytics, the EPYC 9555P’s combination of higher clocks and greater bandwidth makes it the statistically superior option — it wins 10 of 14 head-to-head comparisons.

The Intel Xeon 6781P is the specialist’s choice. Its 58.1% victory in prime number finding and 14.7% win in physics indicate strengths in specific computational patterns, likely benefiting from the 336 MB shared L3 cache. The 136 PCIe Gen 5 lanes (versus 128) offer marginally more I/O expansion headroom. For workloads that stress cache residency — such as certain simulation codes, scientific computing, or in-memory databases — the Intel part’s larger cache and 4.2% edge in extended instructions justify consideration, despite its lower core count efficiency.

The average benchmark scores tell a nuanced story: Intel’s 315,524 average is 1.2% ahead of the AMD EPYC 9575F and 9.9% ahead of the EPYC 9555P’s 287,066. However, the EPYC 9555P’s nearest rivals include the Intel Xeon 696X (0.3% behind), indicating that AMD’s chip sits in a highly competitive cluster. The 80-core Intel part edges out the 64-core AMD chip in aggregate scoring, but the AMD processor wins more individual tests, revealing that Intel’s advantage is concentrated in a few specialized benchmarks while AMD dominates the breadth of common workloads.

For buyers prioritizing raw core count and maximum cache, the Intel Xeon 6781P delivers. For those needing balanced performance across encryption, compression, math, and rendering, the AMD EPYC 9555P is the data-backed winner. Both are 99th-percentile processors, but the EPYC 9555P’s broader benchmark superiority — combined with its earlier release date and higher clock speeds — makes it the more versatile recommendation for most server deployments.