AMD EPYC 8434P vs AMD EPYC 9384X Comparison

FAQ

Q: Which processor has more cores and threads?

A: The AMD EPYC 8434P has 48 cores and 96 threads, while the AMD EPYC 9384X has 32 cores and 64 threads. That is a 16-core and 32-thread advantage for the 8434P.

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

A: The EPYC 9384X leads clearly. In Cinebench R23 single-core it scores 8359 versus 7978 for the 8434P, a 4.6% advantage. The PassMark single-thread gap is larger: 3015 versus 2448, or 18.8% in favor of the 9384X.

Q: Which CPU wins in multi-threaded Cinebench tests?

A: The EPYC 9384X wins every Cinebench multi-core test recorded. In Cinebench R23 multi-core it scores 59215 versus 56516, also a 4.6% edge. The same pattern holds for R15 (5968 vs 5696) and R20 (24870 vs 23736).

Q: Where does the EPYC 8434P dominate?

A: The 8434P wins in several PassMark workloads. It leads data compression by 26.1% (1412835 vs 1119983), data encryption by 33.9% (97254 vs 72631), extended instructions by 15.9% (86189 vs 74363), floating point math by 23.5% (215669 vs 174630), integer math by 29.4% (385290 vs 297833), and random string sorting by 5.4% (125932 vs 119440).

Q: What about the physics workload?

A: The EPYC 9384X is dramatically ahead. Its PassMark physics score is 9332 versus 4036 for the 8434P, a 56.8% gap. This is the largest single-workload difference in the recorded data.

Q: How do their overall average benchmark scores compare?

A: The 8434P has a higher average benchmark score of 146881, placing it in the 98th percentile of all CPUs. The 9384X averages 120427, in the 97th percentile. The 8434P sits close to rivals like the AMD Ryzen Threadripper PRO 9965WX (147009, 0.1% higher) and the AMD Ryzen 9 PRO 9965 (145728, 0.8% lower).

Architecture Differences

The two processors belong to different EPYC families, and the architectural gap shows up immediately. The EPYC 8434P is part of the EPYC 8004 series, built on the Zen 4c architecture with the codename Siena. The EPYC 9384X comes from the EPYC 9004 series, using full Zen 4 with the codename Genoa-X.

Both chips are fabricated on TSMC's 5 nm process, but the similarities end there. The 8434P integrates 35,500 million transistors across a die composed of 4x 73 mm² chiplets. The 9384X packs 90,160 million transistors across 8x 72 mm² chiplets, which reflects its much larger cache array.

Cache is where the 9384X makes its defining statement. It carries 768 MB of shared L3 cache, while the 8434P has 128 MB shared. That is a sixfold difference in L3 capacity, a feature designed for data-heavy workloads that repeatedly access large working sets. Both chips share the same L1 and L2 configuration: 64 KB per core and 1 MB per core respectively.

The 8434P uses AMD Socket SP6, while the 9384X uses AMD Socket SP5. Memory subsystems also diverge sharply. The 8434P supports DDR5 over a six-channel bus with 230.4 GB/s of bandwidth. The 9384X doubles the memory channels to twelve and matches that with 460.8 GB/s of bandwidth. Both support ECC memory.

PCIe connectivity favors the 9384X as well. It provides Gen 5 with 128 lanes (CPU only), while the 8434P offers Gen 5 with 96 lanes (CPU only). Clock speeds follow the same pattern: the 9384X has a base clock of 3.10 GHz and a boost clock of 3.90 GHz, compared to 2.50 GHz base and 3.10 GHz boost for the 8434P.

The 9384X also draws more power, rated at a TDP of 320 watts versus 200 watts for the 8434P. Both chips are actively produced, and neither has an unlocked multiplier.

Head-to-Head Benchmarks

The benchmark data reveals a split personality between these two CPUs. The 9384X controls every Cinebench test, while the 8434P claims most PassMark compute workloads. The margin of victory tells the real story.

In Cinebench R15 multi-core, the 9384X scores 5968 against 5696, a 4.6% lead. Single-core R15 shows the same gap: 842 versus 804, also 4.5% in favor of the 9384X. Moving to R20, the multi-core result is 24870 versus 23736 (4.6% gap), and single-core is 3510 versus 3350 (4.6% gap). R23 repeats the pattern exactly: multi-core 59215 versus 56516, single-core 8359 versus 7978, both with a 4.6% delta. PassMark multithread also goes to the 9384X, with 69665 versus 66490, a 4.6% margin.

The 9384X extends its win column with two more PassMark tests. In find prime numbers, it scores 596 versus 298, a 50% advantage. The physics test is even more lopsided: 9332 versus 4036, or 56.8% ahead. Single-thread performance also belongs to the 9384X, with 3015 versus 2448, an 18.8% gap.

The 8434P answers with a series of decisive wins in PassMark. Data compression is its largest victory: 1412835 versus 1119983, a 26.1% edge. Integer math follows at 29.4% (385290 vs 297833), and floating point math at 23.5% (215669 vs 174630). Data encryption shows a 33.9% lead (97254 vs 72631). Extended instructions come in at 15.9% (86189 vs 74363), and random string sorting at 5.4% (125932 vs 119440).

Counting wins, the 9384X takes 11 benchmarks and the 8434P takes 6. But the average benchmark score tells a different story: the 8434P averages 146881, which is 22% higher than the 9384X's 120427. That discrepancy comes from the 8434P's massive wins in high-throughput PassMark tests, which carry more weight in the average.

The Verdict

The recorded data points to a clear split in suitability. The EPYC 9384X is the pick for single-threaded performance, Cinebench-class rendering, and physics simulation. Its 18.8% single-thread lead and 56.8% physics advantage make it the better choice for workloads that rely on per-core speed and massive L3 cache. The 768 MB L3 cache and twelve-channel memory bandwidth support that positioning.

The EPYC 8434P is the pick for data processing and encryption-heavy tasks. Its 33.9% lead in data encryption and 26.1% lead in data compression show strength in workloads that scale with core count and thread count. The 48-core count, despite lower clocks, drives those wins. Its higher average benchmark score of 146881 versus 120427 also suggests broader general throughput capability.

For buyers deciding between the two, the choice rests on workload type. If the work involves physics, prime number calculations, or single-threaded responsiveness, the 9384X is the stronger option. If the work involves compression, encryption, or integer and floating point math at scale, the 8434P wins.

Specification Differences

| Specification | AMD EPYC 8434P | AMD EPYC 9384X |

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

| Series | EPYC 8004 series | EPYC 9004 series |

| Cores | 48 | 32 |

| Threads | 96 | 64 |

| Base Clock | 2.50 GHz | 3.10 GHz |

| Boost Clock | 3.10 GHz | 3.90 GHz |

| TDP | 200 W | 320 W |

| Socket | AMD Socket SP6 | AMD Socket SP5 |

| Architecture | Zen 4c | Zen 4 |

| Codename | Siena | Genoa-X |

| Transistors | 35,500 million | 90,160 million |

| Die Size | 4x 73 mm² | 8x 72 mm² |

| L3 Cache | 128 MB (shared) | 768 MB (shared) |

| Memory Bus | Six-channel | Twelve-channel |

| Memory Bandwidth | 230.4 GB/s | 460.8 GB/s |

| PCIe | Gen 5, 96 Lanes (CPU only) | Gen 5, 128 Lanes (CPU only) |

| Launch MSRP | $2700 | $5529 |