AMD EPYC 7643P vs Intel Xeon w9-3575X Comparison

The AMD EPYC 7643P and Intel Xeon w9-3575X are two high-core-count workstation processors that sit at nearly identical overall performance levels. The Intel part wins 11 of the 16 head-to-head comparisons, while the AMD part takes 5, but the aggregate benchmark scores tell a story of near-parity: the EPYC 7643P averages 144,824 points against the Xeon’s 144,323, a difference of just 0.3%. Both processors sit in the 98th percentile of all CPUs tracked, placing them at the very top of the performance hierarchy, yet their strengths are distributed across very different workload types.

Head-to-Head Benchmarks

The most decisive single victory belongs to the AMD EPYC 7643P in data encryption, where it scores 95,606 against the Xeon w9-3575X’s 62,258. That is a 53.6% advantage, the largest delta in either direction across the entire comparison. This is not a marginal edge; it suggests the EPYC’s Zen 3 architecture handles cryptographic workloads with substantially greater efficiency, likely due to its larger shared L3 cache and different instruction scheduling.

In integer math, the EPYC 7643P again dominates, posting 390,775 versus the Xeon’s 298,224, a 31% lead. This is a significant win for integer-heavy compute tasks. The EPYC also wins in random string sorting by 19% (160,274 vs 134,723) and in physics by 17.1% (8,002 vs 6,836). These four wins—encryption, integer math, string sorting, and physics—are all substantial, with the smallest margin being the 17.1% physics advantage.

The Intel Xeon w9-3575X, however, takes the remaining 11 benchmarks, and its victories are equally pronounced. The most striking is in extended instructions, where it scores 109,843 versus the EPYC’s 67,398, a 38.6% advantage. This is a clear signal that the Xeon’s AVX-512-style vector extensions are far more capable for floating-point-heavy, SIMD-oriented code. Floating point math follows the same pattern: the Xeon wins 273,398 to 216,592, a 20.8% lead.

In single-threaded performance, the Xeon is decisively faster. Its PassMark single-thread score of 3,672 is 27.7% higher than the EPYC’s 2,655. This gap is consistent across the Cinebench suite: the Xeon leads by 7.3% in both R15 and R20 single-core tests (1,008 vs 934 and 4,200 vs 3,895, respectively). The Xeon’s 4.80 GHz boost clock versus the EPYC’s 3.60 GHz is a key factor here, though the benchmark data itself confirms the outcome.

In multi-threaded workloads, the Xeon also holds a consistent edge, but the margins are smaller. In Cinebench R23 multi-core, the Xeon scores 70,837 against the EPYC’s 65,710, a 7.2% lead. The same 7.2% delta appears in R20 multi-core (29,751 vs 27,598) and R15 multi-core (7,140 vs 6,623). PassMark’s multithread test shows a similar 7.2% advantage for the Xeon (83,338 vs 77,307). The Xeon also wins the find prime numbers test, but by a narrow 5.2% (687 vs 651).

Where Each One Wins

The AMD EPYC 7643P is the clear choice for security and data-processing workloads. Its 53.6% encryption advantage and 31% integer math lead make it the stronger candidate for database operations, compression tasks, and cryptographic functions. The data compression score further reinforces this: the EPYC wins 1,326,051 to 1,219,584, an 8.7% margin. For workloads that involve heavy data shuffling, string manipulation, or physics simulations, the EPYC’s 17-19% leads in random string sorting and physics suggest it handles irregular memory access patterns and branch-heavy code better.

The Intel Xeon w9-3575X is the superior processor for scientific computing and any workload that leverages vectorized instructions. Its 38.6% lead in extended instructions and 20.8% lead in floating-point math make it the obvious pick for numerical simulation, machine learning inference, and rendering tasks that rely on SIMD. The 27.7% single-thread advantage also makes it better for lightly threaded applications, legacy code, or any task where per-core speed matters more than core count. Even in fully multi-threaded synthetic loads like Cinebench, the Xeon consistently outperforms the EPYC by about 7.2%, meaning that for general productivity and rendering, the Xeon is the safer bet.

FAQ

Q: Which processor has the higher average benchmark score?

A: The AMD EPYC 7643P has a slightly higher average score of 144,824, compared to the Intel Xeon w9-3575X’s 144,323, a difference of 0.3%.

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

A: The Intel Xeon w9-3575X leads by 27.7% in PassMark single-thread testing (3,672 vs 2,655) and by 7.3% in both Cinebench R15 and R20 single-core tests.

Q: Which chip is better for encryption workloads?

A: The AMD EPYC 7643P is vastly superior, scoring 95,606 in PassMark data encryption versus the Xeon’s 62,258, a 53.6% advantage.

Q: Does the Xeon w9-3575X win all multi-threaded tests?

A: No. The EPYC wins PassMark multithread-adjacent tests like integer math (31% lead) and physics (17.1% lead), but the Xeon wins the Cinebench multi-core suite and PassMark multithread by roughly 7.2% each.

Q: What is the difference in core counts?

A: The AMD EPYC 7643P has 48 cores and 96 threads, while the Intel Xeon w9-3575X has 44 cores and 88 threads.

Q: Which processor has higher boost clock speeds?

A: The Intel Xeon w9-3575X boosts to 4.80 GHz, while the AMD EPYC 7643P maxes out at 3.60 GHz.

Specification Differences

The two processors diverge significantly in core configuration. The AMD EPYC 7643P packs 48 cores and 96 threads, while the Intel Xeon w9-3575X offers 44 cores and 88 threads. The EPYC has a higher base clock at 2.30 GHz versus 2.20 GHz, but the Xeon has a much higher boost clock at 4.80 GHz versus 3.60 GHz. Thermal design power also differs sharply: the EPYC is rated at 225 W, while the Xeon is rated at 340 W.

Memory support is a major split. The EPYC uses DDR4 with an eight-channel bus and a peak bandwidth of 204.8 GB/s. The Xeon uses DDR5 with an eight-channel bus and a higher peak bandwidth of 307.2 GB/s. PCIe capabilities differ as well: the EPYC provides Gen 4 with 128 lanes (CPU only), while the Xeon provides Gen 5 with 112 lanes (CPU only). The Xeon has an unlocked multiplier, whereas the EPYC does not. The release dates are also different, with the EPYC launching on September 4, 2023, and the Xeon on August 23, 2024.

Architecture Differences

The architectural split is fundamental. The AMD EPYC 7643P is built on Zen 3 architecture, codenamed Milan, part of the EPYC 7003 series, and fabricated on a 7 nm process at TSMC. It uses a chiplet design with 8x 81 mm² dies and 33,200 million transistors. The Intel Xeon w9-3575X is based on Sapphire Rapids, part of the Xeon W generation, fabricated on a 10 nm process at Intel, with a 4x 477 mm² die configuration.

Cache hierarchies are markedly different. The EPYC offers 64 KB of L1 and 512 KB of L2 per core, but its L3 cache is a massive 256 MB shared pool. The Xeon has 80 KB of L1 and 2 MB of L2 per core, but a much smaller 97.5 MB L3 cache. The EPYC’s larger L3 cache likely contributes to its wins in encryption and integer math, where large working sets can be held on-chip. The Xeon’s larger per-core L2 cache and smaller L3 suggest a different trade-off favoring high per-core bandwidth for vectorized code, which aligns with its extended instructions lead.

Both support ECC memory, but the memory type differs as noted. The EPYC’s integrated graphics are not specified, while the Xeon lists integrated graphics as “N/A.” The EPYC is a server/workstation part with an active production status, and the Xeon is likewise active. The launch MSRP for the EPYC is $2722, while the Xeon’s launch MSRP is $3789, but that figure is provided for reference only and does not affect performance analysis.