AMD EPYC 9555P vs AMD Ryzen Threadripper PRO 9985WX Comparison

The AMD Ryzen Threadripper PRO 9985WX and AMD EPYC 9555P are both 64-core, 128-thread Zen 5 processors, yet the benchmark data reveals a distinct split in their performance profiles. The Threadripper PRO 9985WX secures 16 of the 17 head-to-head benchmark wins, while the EPYC 9555P claims a single, notable victory. This pattern indicates that while both are top-tier processors in the 99th percentile of all CPUs, their design priorities lead to different strengths.

Head-to-Head Benchmarks

The Threadripper PRO 9985WX dominates the Cinebench suite with a consistent 15.3% advantage across every test. In Cinebench R23 multi-core, it scores 132,859 against the EPYC’s 115,186, and in single-core it posts 18,756 versus 16,261. This consistency extends to R15 and R20, where the deltas are also 15.3% in both multi-core and single-core runs. The data suggests a uniform clock-for-clock advantage rather than workload-specific scaling.

The Passmark results show an even wider gap in some areas. The most dramatic difference is in single-thread performance, where the Threadripper PRO 9985WX scores 4,482 compared to the EPYC’s 3,410—a 31.4% lead. This is the largest single delta in the entire comparison. Extended instructions also favor the Threadripper PRO 9985WX by 17.9% (225,340 vs 191,082), and random string sorting shows a 17.3% edge (329,014 vs 280,398). Multi-threaded Passmark scores reflect the overall trend, with the Threadripper PRO 9985WX leading 150,071 to 123,576, a 21.4% difference.

However, the EPYC 9555P wins the Passmark physics test decisively. It scores 15,474 against the Threadripper PRO 9985WX’s 13,783, a -10.9% delta in favor of the EPYC. This is an outlier result that suggests a specific workload advantage. In other Passmark tests, the Threadripper PRO 9985WX leads by smaller margins: data compression is 10.4% higher (2,912,972 vs 2,639,400), integer math is 10.9% higher (872,710 vs 787,106), and floating-point math is 13.8% higher (553,348 vs 486,407). Data encryption shows the narrowest gap at 4% (154,824 vs 148,896), and find prime numbers is 6.7% higher (1,138 vs 1,067).

Architecture Differences

Both processors are built on TSMC’s 4 nm process with 66,520 million transistors across 8x 70.6 mm² dies, but their cache layouts differ. The Threadripper PRO 9985WX has 64 KB of L1 cache per core, while the EPYC 9555P has 80 KB per core. Both share 1 MB L2 per core and 256 MB L3, though the EPYC’s L3 is explicitly listed as shared. This L1 difference may contribute to the EPYC’s physics test win, as larger per-core cache can benefit certain data-heavy computations.

Clock speeds are a major differentiator. The Threadripper PRO 9985WX boosts to 5.40 GHz, while the EPYC 9555P tops out at 4.40 GHz—a full 1.0 GHz lower. Both have a 3.20 GHz base clock. This boost advantage explains the Threadripper PRO 9985WX’s 31.4% lead in single-threaded Passmark and its consistent Cinebench single-core wins. The TDP figures differ slightly: the Threadripper PRO 9985WX is rated at 350 W, while the EPYC 9555P is at 360 W.

Memory architecture favors the EPYC 9555P. It uses a twelve-channel memory bus with 576.0 GB/s bandwidth, whereas the Threadripper PRO 9985WX uses eight channels at 409.6 GB/s. Both support DDR5 and ECC memory. The sockets are incompatible: the Threadripper PRO 9985WX uses AMD Socket sTR5, and the EPYC 9555P uses AMD Socket SP5. PCIe is identical at Gen 5 with 128 lanes (CPU only). The Threadripper PRO 9985WX has an unlocked multiplier, while the EPYC 9555P is locked. Release dates differ by roughly nine months, with the EPYC launching first.

Where Each One Wins

The Threadripper PRO 9985WX is the clear choice for single-threaded and lightly-threaded workloads. Its 31.4% lead in Passmark single-thread and 15.3% advantage in Cinebench R23 single-core suggest it will excel in applications that rely on per-core performance, such as legacy software, certain simulation tools, and interactive workstation tasks. The 17.9% edge in extended instructions and 17.3% lead in random string sorting indicate strength in specialized instruction sets and sorting-heavy data processing.

The EPYC 9555P’s win in Passmark physics (15,474 vs 13,783) is its only benchmark victory, but it is a meaningful one. Physics simulations often stress memory bandwidth and cache hierarchies, and the EPYC’s twelve-channel memory bus delivering 576.0 GB/s likely plays a role here. The Threadripper PRO 9985WX’s eight-channel bus at 409.6 GB/s is 29% lower in raw bandwidth, which could bottleneck certain physics or large-data workloads.

For multi-threaded rendering and general compute, the Threadripper PRO 9985WX is consistently ahead. Its 15.3% Cinebench R23 multi-core lead and 21.4% Passmark multi-thread advantage show that its higher boost clock provides benefits even when all 64 cores are active. The EPYC 9555P is not far behind in absolute terms—its Cinebench R23 score of 115,186 is still exceptional—but the Threadripper PRO 9985WX’s 132,859 is decisively higher.

The Verdict

The data points to the AMD Ryzen Threadripper PRO 9985WX as the stronger performer in nearly every measured category. Its 16-1 benchmark win record, highlighted by a 31.4% single-thread lead and 21.4% multi-thread lead, makes it the superior choice for users who prioritize raw CPU speed across a wide range of applications. The 15.3% uniform advantage in Cinebench tests suggests that its higher 5.40 GHz boost clock translates into real-world performance gains beyond just synthetic benchmarks.

The AMD EPYC 9555P is not without merit. Its Passmark physics win indicates that certain memory-bandwidth-sensitive workloads may favor its twelve-channel architecture. The EPYC’s 576.0 GB/s bandwidth versus the Threadripper PRO 9985WX’s 409.6 GB/s is a significant architectural difference that could matter in specific server deployments. However, for general workstation use, rendering, or any workload that values single-thread speed, the Threadripper PRO 9985WX’s data is compelling.

Picking between them should come down to the workload. If the primary tasks involve physics simulations or memory-heavy server workloads, the EPYC 9555P’s physics win and higher bandwidth are notable. For everything else—from 3D rendering to software compilation to interactive work—the Threadripper PRO 9985WX’s benchmark dominance makes it the data-backed choice. The EPYC’s locked multiplier versus the Threadripper PRO 9985WX’s unlocked multiplier is another point in the latter’s favor for enthusiasts.

FAQ

Q: Which processor has the higher boost clock?

A: The AMD Ryzen Threadripper PRO 9985WX boosts to 5.40 GHz, while the AMD EPYC 9555P boosts to 4.40 GHz.

Q: What is the largest performance difference between the two?

A: The largest delta is in Passmark single-thread performance, where the Threadripper PRO 9985WX leads by 31.4% (4,482 vs 3,410).

Q: Did the EPYC 9555P win any benchmarks?

A: Yes, it won the Passmark physics test with a score of 15,474 compared to the Threadripper PRO 9985WX’s 13,783, a -10.9% delta.

Q: How do their memory systems differ?

A: The EPYC 9555P has a twelve-channel memory bus with 576.0 GB/s bandwidth, while the Threadripper PRO 9985WX has an eight-channel bus with 409.6 GB/s.

Q: Are both processors based on the same architecture?

A: Yes, both use Zen 5 architecture on TSMC’s 4 nm process, but with different codenames: Shimada Peak for the Threadripper PRO 9985WX and Turin for the EPYC 9555P.

Q: Do both processors have the same number of cores and threads?

A: Yes, both have 64 cores and 128 threads.

Specification Differences

| Specification | AMD Ryzen Threadripper PRO 9985WX | AMD EPYC 9555P |

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

| Base Clock | 3.20 GHz | 3.20 GHz |

| Boost Clock | 5.40 GHz | 4.40 GHz |

| TDP | 350 W | 360 W |

| Socket | AMD Socket sTR5 | AMD Socket SP5 |

| Codename | Shimada Peak | Turin |

| L1 Cache | 64 KB (per core) | 80 KB (per core) |

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

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

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

| Multiplier | Unlocked | Locked |

| Release Date | 2025-07-22 | 2024-10-09 |

| Launch MSRP | $7999 | $7983 |