Intel Xeon 6521P vs Intel Xeon w7-3555 Comparison

The Intel Xeon w7-3555 and Intel Xeon 6521P are remarkably close competitors, separated by only 0.3% in average benchmark score. The w7-3555 edges ahead in 11 of 17 head-to-head tests, but the 6521P counters with decisive wins in specialized workloads. The w7-3555 is the choice for single-threaded responsiveness and floating-point/extension-heavy compute, while the 6521P dominates compression, encryption, and prime-number workloads. Neither chip is a universal winner; the data points to workload-specific strengths that define their respective use cases.

Where Each One Wins

The Intel Xeon w7-3555 claims victory in every Cinebench test, including single-core and multi-core variants. Its passmark single-thread score of 3549 beats the 6521P’s 3238 by 9.6%, the largest margin in any test. This makes the w7-3555 the better pick for latency-sensitive, lightly threaded applications where per-core performance dictates responsiveness. It also wins floating-point math (190917 vs 178828, a 6.8% edge) and extended instructions (77619 vs 72820, a 6.6% edge), indicating an advantage in scientific computing, simulation, and code that relies on vectorized instruction sets. The w7-3555 also takes the passmark multithread test (67754 vs 66657, a 1.6% margin), reinforcing its all-around compute lead in mixed workloads.

The Intel Xeon 6521P, despite losing the overall average, wins the most specialized tests. Its data compression score of 967721 narrowly beats the w7-3555’s 966970, and its data encryption score of 51221 is 6.3% higher than the w7-3555’s 48007. The biggest gap comes in find prime numbers: the 6521P scores 560 versus 398, a 28.9% advantage. It also wins integer math (246263 vs 244642), physics (5972 vs 5802), and random string sorting (104517 vs 96112, an 8% lead). These results point to workloads involving cryptography, data integrity checks, sorting algorithms, and integer-heavy processing, where the 6521P’s architecture extracts more throughput per operation.

Architecture Differences

The two processors come from different Intel generations and use different manufacturing processes. The w7-3555 is a Sapphire Rapids part built on Intel’s 10 nm node, while the 6521P is a Granite Rapids part on a 5 nm node. The w7-3555 packs 28 cores and 56 threads, versus 24 cores and 48 threads on the 6521P. Despite having fewer cores, the 6521P uses a larger die at 598 mm² compared to the w7-3555’s 4x 477 mm² multi-die setup. The 6521P’s cache layout differs substantially: it offers 112 KB of L1 per core and 144 MB of shared L3, while the w7-3555 provides 80 KB L1 per core and 75 MB of L3. The w7-3555 compensates with a higher boost clock of 4.80 GHz versus 4.10 GHz on the 6521P, and a base clock of 2.70 GHz versus 2.60 GHz. The 6521P counters with a much higher memory bandwidth of 409.6 GB/s versus 307.2 GB/s, both using eight-channel DDR5. The 6521P also offers more PCIe lanes (136 versus 112, both Gen 5) and uses a different socket (Intel Socket 4710 versus Intel Socket 4677). Both have ECC memory support and no integrated graphics. The 6521P’s 5 nm process likely contributes to its efficiency, though power consumption figures are not directly comparable in the data.

Head-to-Head Benchmarks

The w7-3555 wins all six Cinebench tests by a consistent 1.6% margin, including R15 multi-core (5804 vs 5711), R15 single-core (819 vs 806), R20 multi-core (24187 vs 23796), R20 single-core (3414 vs 3359), R23 multi-core (57590 vs 56658), and R23 single-core (8130 vs 7998, a 1.7% edge). This uniformity suggests a clock-speed-driven advantage, as the w7-3555’s 4.80 GHz boost outpaces the 6521P’s 4.10 GHz. In passmark single-thread, the w7-3555 wins decisively at 3549 vs 3238, a 9.6% gap that underscores its per-core superiority.

The 6521P’s wins are larger in magnitude. Its 28.9% lead in find prime numbers (560 vs 398) is the single biggest delta of the comparison. Data encryption shows a 6.3% advantage (51221 vs 48007), and random string sorting an 8% lead (104517 vs 96112). These are not marginal differences; they represent fundamental architectural strengths. The 6521P also edges out the w7-3555 in data compression (967721 vs 966970), integer math (246263 vs 244642), and physics (5972 vs 5802), though those margins are under 3%. The w7-3555’s 6.8% win in floating-point math (190917 vs 178828) and 6.6% win in extended instructions (77619 vs 72820) show it retains a clear edge in number-crunching and SIMD-heavy code.

The Verdict

Pick the Intel Xeon w7-3555 if your primary workloads are single-threaded, floating-point intensive, or require the highest boost clocks. Its 9.6% single-thread lead and 6.8% floating-point advantage make it the superior choice for interactive workstation tasks, legacy single-threaded applications, and scientific simulations that rely on double-precision math. The 28-core/56-thread configuration also ensures it holds up in multi-threaded Cinebench tests, where it leads by 1.6% across the board. This is a balanced processor for general compute with a bias toward per-core performance.

Choose the Intel Xeon 6521P for specialized, integer-heavy or cryptographic workloads. Its 28.9% lead in find prime numbers, 6.3% advantage in data encryption, and 8% edge in random string sorting indicate an architecture optimized for data manipulation, hashing, and algorithmic processing. The 144 MB of shared L3 cache and 409.6 GB/s memory bandwidth likely fuel these wins, making it a better fit for database operations, compression pipelines, and security-focused applications. Its 24-core/48-thread count is lower, but the 6521P still trails the w7-3555 by only 1.6% in multi-core Cinebench, proving its efficiency per core is superior in specific tasks.

FAQ

Q: Which processor has a higher average benchmark score?

A: The Intel Xeon w7-3555 averages 106192, while the Intel Xeon 6521P averages 105845, a 0.3% difference.

Q: How much faster is the w7-3555 in single-threaded tests?

A: The w7-3555 scores 3549 in passmark single-thread, versus 3238 for the 6521P, a 9.6% advantage.

Q: What is the largest benchmark margin between the two?

A: The 6521P wins find prime numbers by 28.9%, scoring 560 versus the w7-3555’s 398.

Q: Do both processors support ECC memory?

A: Yes, both have ECC memory support and use eight-channel DDR5.

Q: How do their core counts differ?

A: The w7-3555 has 28 cores and 56 threads, while the 6521P has 24 cores and 48 threads.

Q: Which processor has more L3 cache?

A: The 6521P has 144 MB of shared L3, while the w7-3555 has 75 MB.

Specification Differences

• Cores: 28 (w7-3555) vs 24 (6521P)
• Threads: 56 (w7-3555) vs 48 (6521P)
• Base Clock: 2.70 GHz (w7-3555) vs 2.60 GHz (6521P)
• Boost Clock: 4.80 GHz (w7-3555) vs 4.10 GHz (6521P)
• Process Node: 10 nm (w7-3555) vs 5 nm (6521P)
• Die Size: 4x 477 mm² (w7-3555) vs 598 mm² (6521P)
• L1 Cache: 80 KB per core (w7-3555) vs 112 KB per core (6521P)
• L3 Cache: 75 MB (w7-3555) vs 144 MB shared (6521P)
• Memory Bandwidth: 307.2 GB/s (w7-3555) vs 409.6 GB/s (6521P)
• PCIe Lanes: 112 (w7-3555) vs 136 (6521P), both Gen 5
• Socket: Intel Socket 4677 (w7-3555) vs Intel Socket 4710 (6521P)
• Codename: Sapphire Rapids (w7-3555) vs Granite Rapids (6521P)
• Generation: Xeon W (Sapphire Rapids) vs Xeon 6 (Granite Rapids-SP)
• Launch MSRP: $2339 (w7-3555) vs $1250 (6521P)