Intel Xeon 6521P vs Intel Xeon 6730P Comparison

FAQ

Q: Which processor has more cores and threads?

A: The Intel Xeon 6730P has 32 cores and 64 threads, while the Intel Xeon 6521P has 24 cores and 48 threads. The 6730P offers 8 additional cores and 16 additional threads.

Q: How do the boost clocks compare between the two?

A: The Intel Xeon 6521P has a higher boost clock of 4.10 GHz, while the Intel Xeon 6730P boosts to 3.80 GHz. The base clocks are close, with the 6521P at 2.60 GHz and the 6730P at 2.50 GHz.

Q: What is the difference in L3 cache capacity?

A: The Intel Xeon 6730P has 288 MB of shared L3 cache, while the Intel Xeon 6521P has 144 MB of shared L3 cache. The 6730P has exactly double the L3 capacity.

Q: Which processor wins in single-threaded PassMark testing?

A: The Intel Xeon 6521P wins in the PassMark single-thread test, scoring 3238 compared to the 6730P's 2995, a 7.5% advantage for the 6521P.

Q: How many benchmark wins does each processor claim in the head-to-head comparison?

A: The Intel Xeon 6730P wins 15 of the 17 recorded head-to-head benchmarks, while the Intel Xeon 6521P wins 2, both of which are the PassMark single-thread tests.

Q: What is the average benchmark score for each processor?

A: The Intel Xeon 6730P has an average benchmark score of 124756, while the Intel Xeon 6521P averages 105845. The 6730P's average is about 17.9% higher.

Architecture Differences

Both processors belong to the Granite Rapids architecture and the Xeon 6 (Granite Rapids-SP) generation, built on Intel's 5 nm process node. They share the same Intel Socket 4710, support DDR5 memory across an eight-channel memory bus, and have identical memory bandwidth of 409.6 GB/s. Both support ECC memory and lack integrated graphics, targeting the server and workstation market segment.

The die configuration is a notable difference. The Intel Xeon 6730P uses a dual-die design with a combined die size of 2x 598 mm², whereas the Intel Xeon 6521P uses a single die of 598 mm². This dual-die arrangement helps explain the 6730P's larger core count and doubled L3 cache.

Per-core cache allocations are identical: 112 KB of L1 and 2 MB of L2 per core on both processors. The shared L3 cache differs significantly, with the 6730P offering 288 MB versus 144 MB on the 6521P. This doubling of L3 cache can benefit workloads with large working sets that require frequent data reuse.

PCIe lane counts also differ. The 6730P provides 88 lanes of Gen 5 PCIe (CPU only), while the 6521P provides 136 lanes. The 6521P offers 48 additional PCIe lanes, which may matter for systems with many expansion cards or high-bandwidth I/O devices.

Power envelopes differ as well. The 6730P has a TDP of 250 watts, while the 6521P has a TDP of 225 watts. The 6730P consumes more power but delivers more cores and cache, while the 6521P runs cooler and offers higher clocks.

The release date is the same for both: February 23, 2025. Both are currently active in production status. The part numbers are SRV5R for the 6730P and SRVNS for the 6521P. Neither processor has an unlocked multiplier.

The Verdict

The data points to a clear split based on workload type. The Intel Xeon 6730P is the stronger choice for heavily parallel, multi-threaded workloads. Its 32 cores, 64 threads, and 288 MB of L3 cache deliver consistent wins across nearly all multi-core benchmarks, often by double-digit percentages. The 6730P also has a higher average benchmark score (124756 versus 105845), placing it at the 97th percentile among all CPUs, same as the 6521P.

The Intel Xeon 6521P is preferable when single-threaded performance matters most. It wins the PassMark single-thread test by 7.5%, and its higher boost clock of 4.10 GHz supports that result. The 6521P also provides more PCIe lanes (136 versus 88), which could be decisive for I/O-intensive server configurations.

For server deployments that prioritize core density, cache capacity, and raw multi-thread throughput, the 6730P is the data-supported pick. For workloads that are lightly threaded, latency-sensitive, or constrained by PCIe expansion needs, the 6521P offers a more favorable profile, along with a lower TDP of 225 watts versus 250 watts.

Specification Differences

| Specification | Intel Xeon 6730P | Intel Xeon 6521P |

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

| Cores | 32 | 24 |

| Threads | 64 | 48 |

| Base Clock | 2.50 GHz | 2.60 GHz |

| Boost Clock | 3.80 GHz | 4.10 GHz |

| TDP | 250 W | 225 W |

| Die Size | 2x 598 mm² | 598 mm² |

| L3 Cache | 288 MB (shared) | 144 MB (shared) |

| PCIe Lanes | Gen 5, 88 Lanes (CPU only) | Gen 5, 136 Lanes (CPU only) |

| Part Number | SRV5R | SRVNS |

Both processors share the same architecture (Granite Rapids), process node (5 nm), foundry (Intel), socket (Intel Socket 4710), memory support (DDR5), memory bus (Eight-channel), memory bandwidth (409.6 GB/s), ECC support (yes), integrated graphics (N/A), market segment (Server/Workstation), production status (Active), release date (2025-02-23), and multiplier lock status (false). The launch MSRP is $3726 for the 6730P and $1250 for the 6521P.

Head-to-Head Benchmarks

The Intel Xeon 6730P wins every Cinebench test by a consistent 11.2% margin. In Cinebench R15 multi-core, the 6730P scores 6349 against 5711 for the 6521P. The single-core R15 test shows 896 versus 806. Moving to R20, multi-core results are 26458 versus 23796, and single-core is 3735 versus 3359. In R23, multi-core reaches 62996 versus 56658, and single-core is 8893 versus 7998. This uniformity across Cinebench versions suggests a stable per-thread advantage for the 6730P in this rendering workload.

PassMark results show a wider spread. The largest delta is in physics, where the 6730P scores 8606 versus 5972, a 44.1% advantage. Extended instructions also show a major gap: 96204 versus 72820, a 32.1% lead. Floating point math favors the 6730P by 26.8% (226838 versus 178828), and prime number finding by 22.5% (686 versus 560). Integer math is 18.1% ahead (290740 versus 246263), data compression 17.6% ahead (1138470 versus 967721), and multithread performance 11.2% ahead (74113 versus 66657). Data encryption shows a 9.3% lead (55964 versus 51221), and random string sorting is 9% ahead (113919 versus 104517).

The only wins for the Intel Xeon 6521P come in the PassMark single-thread and singlethread tests, both scoring 3238 versus 2995 for the 6730P, a 7.5% advantage. This aligns with the 6521P's higher boost clock of 4.10 GHz compared to 3.80 GHz.

Where Each One Wins

The Intel Xeon 6730P dominates in multi-threaded and compute-intensive workloads. Its 44.1% lead in PassMark physics suggests strong floating-point and simulation performance. The 32.1% advantage in extended instructions points to workloads using advanced instruction sets, such as encryption, compression, or scientific computing. The 26.8% lead in floating-point math reinforces this. The 6730P also wins in data compression and integer math, making it suitable for database, analytics, and content-processing tasks that can utilize all 32 cores and 64 threads.

The Intel Xeon 6521P wins specifically in lightly threaded scenarios. The 7.5% PassMark single-thread advantage, combined with the higher 4.10 GHz boost clock, makes it the better fit for latency-sensitive applications that rely on a few fast cores. Its 136 PCIe Gen 5 lanes versus 88 on the 6730P also give it an edge in configurations requiring many high-speed I/O devices, such as storage arrays or network interface cards. The 6521P also runs at a lower TDP of 225 watts, which may be relevant in power-constrained racks.

For mixed workloads, the 6730P's average benchmark score of 124756 versus 105845 for the 6521P indicates a generally higher overall performance level. The 6730P's 288 MB L3 cache, double that of the 6521P, can also reduce memory latency for cache-resident data sets, benefiting repeated access patterns in server workloads. The 6521P, with 144 MB L3 and higher clocks, remains a capable option for single-thread-focused tasks, but the data consistently favors the 6730P for parallel processing.