AMD EPYC 9255 vs Intel Xeon w7-3555 Comparison

The AMD EPYC 9255 and Intel Xeon w7-3555 are both 97th-percentile server/workstation processors, but they achieve that status through very different designs. The EPYC 9255 leans on a modern 4 nm process and high clock speeds, while the Xeon w7-3555 counters with more physical cores and a higher TDP envelope. Head-to-head benchmark data shows the AMD part winning 15 of 17 tests, often by double-digit margins, though the Intel chip secures two notable wins in floating-point and extended-instruction workloads. This analysis breaks down where each processor dominates and who should choose which.

FAQ

Q: Which processor has more cores and threads?

A: The Intel Xeon w7-3555 has 28 cores and 56 threads, versus 24 cores and 48 threads on the AMD EPYC 9255.

Q: How do their boost clocks compare?

A: Both processors have the same 4.80 GHz boost clock, but the AMD EPYC 9255 has a higher base clock of 3.25 GHz compared to the Intel's 2.70 GHz.

Q: Which CPU wins in multi-core rendering tests?

A: The AMD EPYC 9255 wins every Cinebench multi-core test. In Cinebench R23 multi-core, it scores 64318 versus 57590 for the Intel, a 11.7% advantage.

Q: What is the single-thread performance difference?

A: In PassMark single-thread tests, the AMD EPYC 9255 scores 3655, which is 3% higher than the Intel Xeon w7-3555's 3549. The gap is larger in Cinebench R23 single-core, where AMD leads 9080 to 8130.

Q: Are there any tests where the Intel Xeon w7-3555 wins?

A: Yes. The Intel wins in PassMark floating-point math (190917 vs 183367, a 4% lead) and PassMark extended instructions (77619 vs 75185, a 3.1% lead).

Q: How do memory bandwidth specifications differ?

A: The AMD EPYC 9255 supports twelve-channel DDR5 memory with 576.0 GB/s bandwidth, while the Intel Xeon w7-3555 uses eight-channel DDR5 with 307.2 GB/s.

The Verdict

The benchmark data presents a clear overall winner: the AMD EPYC 9255 takes 15 of 17 head-to-head tests, with an average benchmark score of 116388 compared to the Intel's 106192. The AMD part's advantage is not marginal in most workloads—it leads by 11.7% across all six Cinebench tests, 25.3% in integer math, and a massive 67.9% in physics simulation. For anyone running general-purpose compute, rendering, encryption, or compression tasks, the EPYC 9255 is the stronger choice based on this data.

However, the Intel Xeon w7-3555 is not without merit. It wins in floating-point math and extended instructions, suggesting an edge in scientific or financial workloads that rely heavily on those operations. The Intel chip also offers 4 more cores and 8 more threads, which could be relevant for highly parallel workloads that scale perfectly with core count, even if current benchmarks show the AMD chip handling most multi-threaded tasks better. The Intel part also has a lower launch MSRP of $2339 versus AMD's $2495, though the performance delta in most tests far exceeds the price difference.

The verdict depends on workload. If the priority is maximum performance across a broad range of tasks—especially single-threaded responsiveness, integer-heavy operations, and memory-bandwidth-bound work—the AMD EPYC 9255 is the data-backed pick. If the specific workload is dominated by floating-point or extended-instruction execution, the Intel Xeon w7-3555 deserves consideration, as does its higher core count for niche scaling scenarios.

Head-to-Head Benchmarks

The most striking pattern in the head-to-head data is the uniform 11.7% delta across all Cinebench tests. From R15 multicore (6483 vs 5804) to R23 single-core (9080 vs 8130), the AMD EPYC 9255 maintains an identical relative advantage. This consistency suggests a fundamental architectural efficiency edge rather than workload-specific tuning.

The PassMark results reveal where the AMD chip truly separates itself. In integer math, the EPYC 9255 scores 306442 versus 244642 for the Intel, a 25.3% lead. Data encryption shows an even larger gap: 59668 vs 48007, a 24.3% advantage for AMD. Random string sorting goes to AMD by 34.4% (129202 vs 96112). The standout is physics simulation, where AMD scores 9740 versus 5802, a 67.9% margin that dwarfs every other test.

The Intel Xeon w7-3555's two wins are worth examining closely. In floating-point math, it scores 190917 against AMD's 183367, a 4% edge. In extended instructions, it leads 77619 to 75185, a 3.1% difference. These are meaningful but narrow victories, especially compared to the double-digit losses the Intel chip suffers elsewhere.

Single-thread performance deserves attention because it affects everyday responsiveness. The AMD EPYC 9255 leads 3655 to 3549 in PassMark single-thread (3% delta) and 9080 to 8130 in Cinebench R23 single-core (11.7% delta). The larger Cinebench gap suggests the AMD architecture has a stronger per-core capability at identical boost clocks.

Specification Differences

The core and thread count difference is the most obvious spec gap: Intel provides 28 cores and 56 threads, while AMD offers 24 cores and 48 threads. This gives the Intel chip a 16.7% core advantage on paper, yet it loses most multi-threaded benchmarks, indicating the AMD cores are substantially more efficient.

Clock speeds favor AMD. The EPYC 9255 runs at a 3.25 GHz base clock versus 2.70 GHz for the Xeon w7-3555, a 20% higher base frequency. Both boost to 4.80 GHz, but the higher base clock means AMD maintains an advantage even when boost isn't fully engaged.

Memory architecture is a major divider. The AMD chip features twelve-channel DDR5 with 576.0 GB/s bandwidth, while the Intel uses eight-channel DDR5 with 307.2 GB/s. That's an 87.5% bandwidth advantage for AMD, explaining its dominance in memory-sensitive tasks like encryption and string sorting.

PCIe lanes also differ: AMD provides 128 Gen 5 lanes (CPU only) versus Intel's 112 Gen 5 lanes. The AMD chip draws 200W TDP versus 325W for Intel, a 62.5% higher power draw for the Intel part. Process node and die size differ dramatically: AMD uses a 4 nm TSMC process with 4x 70.6 mm² dies, while Intel uses a 10 nm process with 4x 477 mm² dies. The Intel chip carries a 75 MB L3 cache and 2 MB per-core L2, while AMD has 128 MB shared L3 and 1 MB per-core L2.

Architecture Differences

The AMD EPYC 9255 is built on Zen 5 architecture, codenamed Turin, part of the EPYC 9005 series. It uses a 4 nm process from TSMC, with 33,260 million transistors spread across 4x 70.6 mm² dies. The Intel Xeon w7-3555 uses Sapphire Rapids architecture on a 10 nm Intel process, with 4x 477 mm² dies. This process node difference—4 nm versus 10 nm—explains much of the performance gap, as AMD achieves higher clock speeds and better efficiency with a more advanced manufacturing process.

Cache hierarchies highlight different design philosophies. AMD allocates 1 MB of L2 per core and 128 MB of shared L3, while Intel provides 2 MB of L2 per core but only 75 MB of L3. The AMD chip's larger L3 cache likely contributes to its strong performance in data-heavy workloads like random string sorting and integer math, where it leads by 34.4% and 25.3% respectively.

Both processors support DDR5 memory with ECC, but AMD's twelve-channel implementation offers nearly double the bandwidth of Intel's eight-channel setup. The PCIe configuration also favors AMD, with 128 Gen 5 lanes versus 112. Neither chip includes integrated graphics, making them pure compute parts for server or workstation use. The AMD EPYC 9255 released on 2024-10-09, while the Intel Xeon w7-3555 came out earlier on 2024-08-23.

Where Each One Wins

The AMD EPYC 9255 is the clear winner for multi-threaded compute workloads. It dominates Cinebench R15, R20, and R23 multi-core tests by 11.7%, and leads PassMark multithread by 13% (76580 vs 67754). The physics simulation benchmark shows a 67.9% advantage, indicating exceptional performance for simulation or gaming-physics-type workloads. AMD also wins decisively in integer math (25.3%), data encryption (24.3%), and random string sorting (34.4%), making it the better choice for general-purpose compute, database operations, and security-related tasks.

Memory-bandwidth-hungry applications strongly favor the AMD chip. With 576.0 GB/s bandwidth versus 307.2 GB/s, the EPYC 9255 handles data compression (5.4% lead) and data encryption (24.3% lead) more effectively. The higher base clock of 3.25 GHz also gives AMD an edge in latency-sensitive or lightly threaded workloads, as shown by its wins in all single-core tests.

The Intel Xeon w7-3555 wins in two specific areas: floating-point math (190917 vs 183367) and extended instructions (77619 vs 75185). These results suggest it is the better option for scientific computing, engineering simulations, or financial modeling that relies heavily on floating-point operations. The Intel chip's 28 cores and 56 threads also provide raw thread-count headroom for workloads that can perfectly utilize every available thread, though current benchmark data shows the AMD chip matching or exceeding this performance with fewer cores.

For single-threaded tasks, the AMD EPYC 9255 wins by 3% in PassMark and 11.7% in Cinebench R23. The Intel chip's only single-thread wins would need to come from workloads not represented in this benchmark set. Overall, the AMD EPYC 9255 is the recommended choice for most users, while the Intel Xeon w7-3555 should be considered specifically for floating-point or extended-instruction-heavy environments where its narrow wins can be leveraged.