AMD EPYC 9455P vs AMD EPYC 9634 Comparison

The AMD EPYC 9634 and AMD EPYC 9455P are both 99th-percentile server processors, but the data shows they are built for different workloads. The 9634, a Zen 4 Genoa part with 84 cores, dominates in data manipulation and encryption, while the 9455P, a Zen 5 Turin part with 48 cores, wins the majority of raw compute and single-threaded tests. The benchmark results are not a simple core-count story; the newer architecture of the 9455P delivers higher per-core performance, yet the massive core advantage of the 9634 still wins in memory-bandwidth-sensitive tasks.

Head-to-Head Benchmarks

The most decisive victories belong to the AMD EPYC 9634 in three specific PassMark tests. Its lead is largest in data encryption, where it scores 151,943 against the 9455P’s 115,202, a 31.9% advantage. This is a clear signal for workloads that rely heavily on cryptographic operations. The 9634 also wins integer math by 19.7% (725,356 vs 606,087) and data compression by 15.7% (2,236,412 vs 1,932,632). These wins are directly attributable to its 84 cores and 384 MB of shared L3 cache, which provide a substantial throughput advantage for parallel data processing.

The AMD EPYC 9455P counters with a sweep of all six Cinebench tests. Across Cinebench R15, R20, and R23, it wins both single-core and multi-core by a consistent 7.5% margin. The scores tell the story: 9,248 vs 9,999 in R15 multi-core, 38,535 vs 41,666 in R20 multi-core, and 91,752 vs 99,206 in R23 multi-core. This consistency indicates a fundamental per-core performance advantage from the Zen 5 architecture, not just a boost-clock difference. The 9455P’s 4.40 GHz boost clock, higher than the 9634’s 3.70 GHz, is a factor, but the architectural efficiency is the primary driver.

The 9455P also wins the PassMark multithread test by 7.5% (116,713 vs 107,944) and the physics test by a massive 26.2% (16,647 vs 12,291). The physics result is the largest single delta in the entire benchmark suite, highlighting a significant advantage in simulation and physics-based compute. In single-threaded performance, the 9455P is equally dominant, scoring 3,750 against the 9634’s 2,924, a 22% lead. This is a critical metric for database queries and other latency-sensitive operations.

The remaining tests are closer. Extended instructions go to the 9455P by a razor-thin 0.7% (138,505 vs 137,543), and floating-point math goes to the 9455P by 1.4% (358,673 vs 353,784). The 9634 wins find prime numbers and random string sorting by 8% each (1,176 vs 1,089 and 261,134 vs 241,849, respectively). Overall, the head-to-head tally is 12 wins for the 9455P and 5 for the 9634, but the magnitude of the 9634’s wins in encryption and integer math makes it a formidable opponent for specific tasks.

FAQ

Q: Which processor has higher multi-core performance?

A: The AMD EPYC 9455P wins every Cinebench multi-core test by 7.5%, including a score of 99,206 vs 91,752 in Cinebench R23. It also wins the PassMark multithread test by 7.5% (116,713 vs 107,944).

Q: Is the AMD EPYC 9634 better at any computationally intensive task?

A: Yes, the 9634 wins data encryption by 31.9% (151,943 vs 115,202) and integer math by 19.7% (725,356 vs 606,087). These are significant margins that suggest a clear advantage for specific server roles.

Q: How large is the single-threaded performance gap?

A: The 9455P is 22% faster in PassMark single-thread (3,750 vs 2,924) and 7.5% faster in Cinebench R23 single-core (14,005 vs 12,953).

Q: What is the core count difference?

A: The EPYC 9634 has 84 cores and 168 threads, while the EPYC 9455P has 48 cores and 96 threads. The 9634 has 36 more cores and 72 more threads.

Q: Which processor has more cache?

A: The EPYC 9634 has 384 MB of shared L3 cache, while the EPYC 9455P has 256 MB of shared L3 cache. The 9634 also has 64 KB of L1 cache per core versus 80 KB per core on the 9455P, but the 9455P has a larger total L1 footprint due to its architecture.

Q: Do both processors support the same memory and PCIe?

A: Yes, both support DDR5 memory, twelve-channel memory buses, and Gen 5 PCIe with 128 lanes. The memory bandwidth differs, however: the 9634 has 460.8 GB/s, while the 9455P has 576.0 GB/s.

Architecture Differences

The fundamental architectural split is between Zen 4 and Zen 5. The EPYC 9634 uses the Zen 4 architecture on a 5 nm process, while the 9455P uses Zen 5 on a 4 nm process, both fabricated by TSMC. This node shrink contributes to the 9455P’s higher efficiency, despite its higher TDP of 300 W versus the 9634’s 290 W. The 9634 is built on the Genoa codename, and the 9455P on Turin, representing two distinct generations of EPYC design.

The transistor counts differ significantly: the 9634 has 78,840 million transistors across 12 chiplets (12x 72 mm² each), while the 9455P has 66,520 million transistors across 8 chiplets (8x 70.6 mm² each). This means the 9634 has more transistors and chiplets, but the 9455P has a denser, newer process. The cache hierarchy also reflects the architectural change: the 9634 has 64 KB of L1 per core, while the 9455P increases this to 80 KB per core. Both have 1 MB of L2 per core, but the 9634’s 384 MB L3 is 50% larger than the 9455P’s 256 MB.

The launch dates show a two-year gap, with the 9634 released on 2022-11-09 and the 9455P on 2024-10-09. This generation gap is the root cause of the performance differences observed. The 9455P’s newer architecture delivers better instructions per clock, which is why it can beat a processor with 36 more cores in many tests.

Specification Differences

The most obvious difference is core count: 84 cores and 168 threads on the 9634 versus 48 cores and 96 threads on the 9455P. Clock speeds also diverge sharply. The 9634 has a 2.25 GHz base clock and 3.70 GHz boost, while the 9455P has a 3.15 GHz base and 4.40 GHz boost. The 9455P is faster in both metrics, with a 0.90 GHz higher base and 0.70 GHz higher boost.

Thermals are close but favor the 9634: it has a 290 W TDP versus the 9455P’s 300 W. Memory bandwidth is a clear win for the 9455P, which offers 576.0 GB/s against the 9634’s 460.8 GB/s. The process node differs (5 nm vs 4 nm), and the architecture differs (Zen 4 vs Zen 5). The 9634 has 78,840 million transistors and a 12x 72 mm² die size, while the 9455P has 66,520 million transistors and an 8x 70.6 mm² die size. The L3 cache differs (384 MB vs 256 MB), and the L1 cache per core differs (64 KB vs 80 KB).

The launch MSRP for the 9634 is $10304, and for the 9455P it is $4819. Both use the AMD Socket SP5, support DDR5, have twelve-channel memory buses, offer 128 PCIe Gen 5 lanes, and support ECC memory. Neither has integrated graphics, and both are locked (multiplier unlocked is false for both). The part numbers are 100-100000797 for the 9634 and 100-000001563 for the 9455P.

Where Each One Wins

The AMD EPYC 9634 wins in scenarios that require massive parallel data throughput. Its 31.9% lead in data encryption makes it the clear choice for security-focused workloads like VPN gateways, SSL/TLS termination, and storage encryption. The 19.7% win in integer math is relevant for database operations, financial modeling, and any integer-heavy analytics. The 8% wins in find prime numbers and random string sorting point to strengths in scientific computing and sorting algorithms. The 9634’s 84 cores and larger L3 cache are the key enablers for these wins.

The AMD EPYC 9455P wins in general-purpose compute and single-threaded performance. Its 26.2% lead in the PassMark physics test makes it superior for simulation, ray tracing, and physics engines. The 22% single-thread lead is critical for latency-sensitive applications like web servers, database query handling, and legacy single-threaded code. The 7.5% win across all Cinebench tests indicates a strong generational improvement that benefits rendering, video encoding, and 3D modeling. The 9455P also wins multithread performance despite having fewer cores, proving that its Zen 5 architecture is more efficient at scaling threaded workloads.

The 9455P’s higher memory bandwidth (576.0 GB/s vs 460.8 GB/s) and higher boost clock (4.40 GHz vs 3.70 GHz) give it an edge in memory-bound and bursty workloads. The 9634, with its lower base clock (2.25 GHz) but more cores, excels at sustained, massively parallel throughput. In a head-to-head of 17 benchmarks, the 9455P wins 12, but the 9634’s wins are often by larger margins in specific, high-value areas.

The Verdict

The data is clear: the AMD EPYC 9455P is the better overall performer. It wins 12 of 17 benchmarks, including all Cinebench tests, and has a 22% single-thread lead. Its average benchmark score of 218,063 is 12% higher than the 9634’s 244,274? No, the data shows the 9634 has a higher average score of 244,274, while the 9455P has 218,063. This means the 9634 still holds the overall average advantage, despite losing the majority of individual tests. This is because the 9634’s wins in data compression, encryption, and integer math are so large that they lift its average score above the 9455P’s.

Therefore, the verdict depends on the workload. For users who need maximum encryption performance, integer math, or data compression, the AMD EPYC 9634 is the data-backed choice. Its 31.9% encryption lead and 19.7% integer math lead are not trivial. For all other workloads, the AMD EPYC 9455P is superior. It offers better single-thread, physics, and multi-core rendering performance, all while using a newer architecture and a higher memory bandwidth. The 9455P is the more versatile processor, while the 9634 is a specialized tool for specific high-throughput tasks.

The average benchmark scores confirm the 9634 is the higher-performing overall part. The 9634’s 244,274 average is 12% above the 9455P’s 218,063. This places the 9634 in a different league, as its nearest rivals include the EPYC 9684X (-8.5%) and the EPYC 9565 (-14.4%). The 9455P, conversely, is 11.9% above the Intel Xeon 6741P and 16.2% above the Intel Xeon 6740E, showing it competes in a lower performance tier. The choice is not which processor is better, but which set of benchmark wins is more valuable for the specific server role.