AMD EPYC 4585PX vs AMD Ryzen Threadripper PRO 9955WX Comparison

The AMD Ryzen Threadripper PRO 9955WX and AMD EPYC 4585PX are both 16-core, 32-thread Zen 5 processors on TSMC's 4 nm node, but they target entirely different platforms and usage models. The benchmark data shows a clear split: the EPYC 4585PX wins the majority of tests with 13 wins against 4 for the Threadripper, yet the Threadripper's average benchmark score of 101,041 edges out the EPYC's 99,324 by 1.7%. This paradox — a lower win count but a higher overall average — comes down to the magnitude of specific workloads, making the choice between them dependent on whether you prioritize raw compute throughput or platform-level capabilities.

Head-to-Head Benchmarks

The EPYC 4585PX dominates the Cinebench suite across the board. In Cinebench R23 multi-core, it scores 60,451 against the Threadripper's 59,494, a 1.6% advantage. The same delta appears in single-core: 8,534 versus 8,399, also 1.6% in favor of the EPYC. This pattern repeats in Cinebench R20 (25,389 vs 24,987 multi-core; 3,584 vs 3,527 single-core) and R15 (6,093 vs 5,996 multi-core; 860 vs 846 single-core). The consistency of the 1.6% gap across all Cinebench versions suggests the EPYC's higher boost clock of 5.70 GHz, compared to the Threadripper's 5.40 GHz, provides a steady advantage in both lightly and heavily threaded rendering workloads.

The EPYC's wins extend into PassMark's integer-heavy and physics-based tests. The most dramatic difference appears in PassMark find prime numbers, where the EPYC scores 547 versus the Threadripper's 337 — a massive 38.4% lead. Similarly, PassMark physics shows the EPYC at 6,612 versus 4,156, a 37.1% gap. These are not marginal wins; they indicate the EPYC's architecture handles certain mathematical and simulation workloads with significantly greater efficiency. The EPYC also wins PassMark integer math (248,563 vs 236,120, a 5% lead), data encryption (47,224 vs 44,389, a 6% lead), and multithread (68,908 vs 67,035, a 2.7% lead).

The Threadripper PRO 9955WX, however, claims the workloads where memory bandwidth and extended instruction efficiency matter. Its most decisive win is PassMark extended instructions at 76,363 versus 69,457, a 9.9% margin. It also wins PassMark data compression (920,954 vs 884,774, a 4.1% lead) and random string sorting (99,813 vs 95,210, a 4.8% lead). In floating point math, the Threadripper takes a narrow 2% win (156,215 vs 153,219). The Threadripper's eight-channel memory bus, delivering 409.6 GB/s compared to the EPYC's dual-channel 89.6 GB/s, likely explains its superiority in data movement-intensive tasks like compression and sorting, despite the EPYC's clock speed advantage.

The single-thread PassMark tests are essentially a tie: 4,538 for the EPYC versus 4,530 for the Threadripper, a 0.2% difference that falls within noise. Overall, the EPYC wins 13 of 17 head-to-head tests, but its losses in compression, extended instructions, floating point, and sorting are often by larger margins than its wins in Cinebench, which explains why its average benchmark score remains slightly lower than the Threadripper's.

The Verdict

The data clearly favors the AMD EPYC 4585PX for users who prioritize raw computational speed per core and consistent performance across rendering and simulation workloads. Its Cinebench wins across all versions, combined with the enormous margins in prime number finding (38.4%) and physics (37.1%), make it the stronger choice for scientific computing, financial modeling, or any workload that stresses integer arithmetic and physical simulation. The EPYC's 170 W TDP, compared to the Threadripper's 350 W, also means it achieves these results at less than half the thermal envelope, a significant operational advantage in dense server environments. Its launch MSRP is $699.

The AMD Ryzen Threadripper PRO 9955WX is the better pick for workloads that depend on memory bandwidth and complex instruction sets. Its 128 PCIe Gen 5 lanes (versus the EPYC's 24) and eight-channel memory support make it the superior platform for large-scale data processing, virtualization with many I/O devices, or content creation pipelines that involve heavy data compression and sorting. The Threadripper's wins in extended instructions (9.9%), data compression (4.1%), and random string sorting (4.8%) point to its strength in database operations, file archiving, and code compilation. Its launch MSRP is $1649.

For a single-socket workstation that must handle both simulation and data-heavy tasks, the Threadripper's higher average benchmark score (101,041 vs 99,324) suggests it offers slightly better overall versatility, despite losing more individual tests. The EPYC, however, is the clear winner if your primary metric is Cinebench rendering or physics-based workloads, where its consistent 1.6% to 37.1% advantages make it the more efficient processor for those specific tasks.

FAQ

Q: Which processor is faster in Cinebench R23 multi-core?

A: The AMD EPYC 4585PX scores 60,451, beating the AMD Ryzen Threadripper PRO 9955WX's 59,494 by 1.6%.

Q: How large is the performance gap in PassMark physics?

A: The EPYC 4585PX scores 6,612, while the Threadripper PRO 9955WX scores 4,156 — a 37.1% difference in favor of the EPYC.

Q: Does the Threadripper win any benchmark by a large margin?

A: Yes, the Threadripper wins PassMark extended instructions by 9.9% (76,363 vs 69,457) and data compression by 4.1% (920,954 vs 884,774).

Q: How do the average benchmark scores compare?

A: The Threadripper PRO 9955WX has an average benchmark score of 101,041, which is 1.7% higher than the EPYC 4585PX's 99,324.

Q: What is the difference in single-thread PassMark scores?

A: The EPYC scores 4,538 and the Threadripper scores 4,530, a negligible 0.2% difference.

Q: Which processor has more benchmark wins?

A: The EPYC 4585PX wins 13 of the 17 head-to-head tests, while the Threadripper wins 4.

Specification Differences

The most glaring specification difference is memory support. The AMD Ryzen Threadripper PRO 9955WX uses an eight-channel DDR5 memory bus with a bandwidth of 409.6 GB/s, while the AMD EPYC 4585PX uses a dual-channel DDR5 bus with 89.6 GB/s bandwidth — a 4.6x difference in theoretical memory throughput. This directly explains the Threadripper's wins in bandwidth-sensitive benchmarks.

The TDP figures diverge significantly: the Threadripper is rated at 350 W, while the EPYC is rated at 170 W. Clock speeds also differ, with the Threadripper having a higher base clock of 4.50 GHz versus the EPYC's 4.30 GHz, but the EPYC has a higher boost clock of 5.70 GHz versus the Threadripper's 5.40 GHz.

The socket and platform are entirely different: the Threadripper uses AMD Socket sTR5, while the EPYC uses AMD Socket AM5. PCIe lane counts are another major split, with the Threadripper offering 128 Gen 5 lanes (CPU only) versus the EPYC's 24 Gen 5 lanes (CPU only). The Threadripper has an unlocked multiplier, while the EPYC does not. The Threadripper has no integrated graphics, whereas the EPYC includes Radeon Graphics. The Threadripper's release date is 2025-07-22, while the EPYC's is 2025-05-12.

Architecture Differences

Both processors are built on Zen 5 architecture at TSMC's 4 nm node, with the same transistor count of 16,630 million and the same die size of 2x 70.6 mm². However, the cache configurations differ. The Threadripper PRO 9955WX has 64 KB of L1 cache per core and 64 MB of L3 cache. The EPYC 4585PX has 80 KB of L1 cache per core and 128 MB of L3 cache — double the L3 capacity. Both have 1 MB of L2 cache per core.

The codenames and generations differ: the Threadripper is codenamed "Shimada Peak" and listed under the Ryzen Threadripper (Zen 4 (Storm Peak)) generation, while the EPYC is codenamed "Grado" and listed under EPYC (Zen 5 (Grado)). The Threadripper is classified as a Desktop market segment product, while the EPYC is classified as Server/Workstation. Both support ECC memory and DDR5, but their memory channels and bandwidths diverge as noted above. The Threadripper's part number is 100-000000725, while the EPYC's is 100-000001561.

Where Each One Wins

The AMD Ryzen Threadripper PRO 9955WX is the winner in data compression, extended instructions, floating point math, and random string sorting. These workloads are all memory-bandwidth or instruction-throughput limited, and the Threadripper's 409.6 GB/s eight-channel memory bus provides the necessary data flow. This makes it the better processor for database compression, file archiving, scientific floating-point calculations, and any workload involving complex vectorized instructions. Its 128 PCIe Gen 5 lanes also make it the superior choice for systems with many high-speed storage devices or GPUs, though the benchmark data does not directly test I/O throughput.

The AMD EPYC 4585PX wins in every Cinebench test (R15, R20, R23, both multi-core and single-core), PassMark data encryption, find prime numbers, integer math, multithread, physics, and single-thread tests. Its higher boost clock of 5.70 GHz and larger 128 MB L3 cache give it an edge in latency-sensitive and integer-heavy tasks. The massive 38.4% lead in prime number finding and 37.1% lead in physics make it the clear choice for computational mathematics, physics simulations, and cryptographic workloads. Its lower 170 W TDP also makes it the better selection for power-constrained environments where per-watt performance is critical, even though the benchmark scores themselves do not include efficiency metrics. The EPYC's wins in Cinebench multi-core tests, despite having dual-channel memory, suggest that rendering workloads are not memory-bandwidth limited at this core count, making the Threadripper's memory advantage irrelevant for those tasks.