Intel Xeon 6511P vs Intel Xeon 6515P Comparison

Head-to-Head Benchmarks

The benchmark data between the Intel Xeon 6511P and the Intel Xeon 6515P shows a clear split. Across the 17 recorded tests, the Xeon 6511P wins 12, while the Xeon 6515P wins 5. The most decisive victories belong to the 6511P, but the 6515P has its own areas of dominance.

In Cinebench testing, the 6511P is consistently ahead by exactly 6.9% in all six runs. The R15 multicore score is 4152 versus 3885, and the R15 singlecore score is 586 versus 548. The R20 multicore test shows 17302 against 16189, with the singlecore at 2442 versus 2285. The R23 multicore run reaches 41196 compared to 38547, while singlecore sits at 5815 versus 5442. This uniform 6.9% delta across every Cinebench test indicates a stable clock-driven advantage rather than workload-specific behavior.

PassMark integer math is another major win for the 6511P, scoring 162524 against 147047, a 10.5% margin. Data compression also favors the 6511P: 640808 versus 592645, a delta of 8.1%. The physics test shows the largest gap in the entire comparison, with the 6511P scoring 4678 against 3829, a 22.2% lead. Random string sorting goes to the 6511P at 67809 versus 64425, a 5.3% edge. Data encryption is closer, with the 6511P at 31429 versus 30476, just 3.1% ahead. The multithread score is nearly identical, 45687 versus 45350, a marginal 0.7% advantage for the 6511P.

The 6515P counters in a few specific workloads. The most striking reversal is in PassMark single-thread performance, where the 6515P scores 2855 against 2545, a 10.9% lead. Prime number finding strongly favors the 6515P, 385 versus 308, a 20% advantage. Extended instructions go to the 6515P at 53383 versus 50730, a 5% edge. Floating-point math is a slim win for the 6515P, 128954 versus 127307, just 1.3% ahead.

The overall average benchmark score reflects this split, with the 6511P at 71051 and the 6515P at 67006. The 6511P sits at the 94th percentile among all CPUs, while the 6515P is at the 93rd. Both are strong server parts, but the data shows the 6511P has the higher aggregate performance.

Where Each One Wins

The Xeon 6511P is the choice for multi-threaded throughput work. Its Cinebench sweep across R15, R20, and R23, both single and multi-core, shows a consistent advantage that will show up in rendering, video encoding, and other threaded workloads. The physics test at 22.2% ahead is particularly telling for simulation and scientific computing, where physics engines and rigid-body calculations dominate. Integer math at 10.5% ahead also points to general-purpose compute, database work, and financial modeling, where integer operations are the bottleneck. Data compression at 8.1% higher and random string sorting at 5.3% higher both favor the 6511P for storage-heavy or log-processing workloads. Encryption performance is modestly better as well, at 3.1% ahead.

The Xeon 6515P is the better option for single-threaded responsiveness and specific math functions. Its PassMark single-thread score of 2855 versus 2545 is a substantial 10.9% margin, which matters for legacy applications that rely on one core or lightly threaded code. The prime number test, at 20% ahead, shows an advantage in certain number-crunching algorithms. Extended instruction throughput, 5% higher, benefits workloads using AVX and similar instruction sets. Floating-point math is essentially tied, with the 6515P just 1.3% ahead.

The multithread score being nearly identical (0.7% apart) suggests that when all cores are saturated with generic parallel work, the two chips are close. The differences appear in specific instruction patterns and single-core frequency behavior.

Architecture Differences

Both processors share the same fundamental architecture. They are built on the Granite Rapids architecture, part of the Xeon 6 generation (Granite Rapids-SP), using Intel as the foundry on a 5 nm process node. Both have 16 cores and 32 threads, with a base clock of 2.30 GHz. The L1 cache is 112 KB per core, L2 is 2 MB per core, and L3 is 72 MB shared. Both support DDR5 memory over an eight-channel bus with 409.6 GB/s of bandwidth, and both have ECC memory support. Neither has integrated graphics, and neither has an unlocked multiplier. Both were released on the same date and are currently marked as Active in production.

The key architectural difference is the boost clock. The 6511P boosts to 4.20 GHz, while the 6515P boosts to 3.80 GHz. This 0.4 GHz gap explains the 6511P's consistent 6.9% lead in Cinebench tests, which are heavily clock-sensitive. The 6515P compensates with a different PCIe configuration: the 6511P offers Gen 5 with 136 lanes (CPU only), while the 6515P offers Gen 5 with 88 lanes (CPU only). This is a significant difference for systems that need maximum expansion, such as GPU servers or storage arrays that require many PCIe lanes.

Both parts have a TDP of 150 watts and use the Intel Socket 4710. The part numbers differ, with the 6511P identified as SRVU9 and the 6515P as SRVU6.

FAQ

Q: Which processor has the higher boost clock?

A: The Intel Xeon 6511P boosts to 4.20 GHz, while the Intel Xeon 6515P boosts to 3.80 GHz. The 6511P's higher boost clock is the primary driver of its 6.9% advantage in all Cinebench tests.

Q: Do both processors have the same core and thread counts?

A: Yes, both have 16 cores and 32 threads. They also share the same base clock of 2.30 GHz, the same L1, L2, and L3 cache sizes, and the same 150 watt TDP.

Q: Which processor is better for single-threaded workloads?

A: The PassMark single-thread test shows the 6515P ahead at 2855 versus 2545, a 10.9% lead. However, the Cinebench single-core tests show the 6511P ahead by 6.9% in each case. The PassMark test measures a different workload pattern, so the choice depends on the specific application.

Q: What is the memory bandwidth of these processors?

A: Both support DDR5 memory over an eight-channel bus, delivering 409.6 GB/s of memory bandwidth. Both also support ECC memory.

Q: How many PCIe lanes does each processor provide?

A: The 6511P provides Gen 5 with 136 lanes (CPU only), while the 6515P provides Gen 5 with 88 lanes (CPU only). This is a major difference for systems requiring many expansion slots or high-bandwidth interconnect.

Q: Which processor has a higher average benchmark score?

A: The 6511P has an average benchmark score of 71051, while the 6515P has an average of 67006. The 6511P also ranks at the 94th percentile among all CPUs, compared to the 93rd percentile for the 6515P.

The Verdict

The data points to the Intel Xeon 6511P as the stronger overall performer. It wins 12 of 17 head-to-head tests, holds a higher average benchmark score (71051 versus 67006), and ranks at a higher percentile (94th versus 93rd). Its Cinebench sweep, physics lead of 22.2%, and integer math advantage of 10.5% make it the better choice for multi-threaded server workloads, scientific computing, and general-purpose compute tasks.

The Xeon 6515P should be selected when single-thread performance matters most, as its PassMark single-thread score is 10.9% higher. It also wins in prime number finding (20% ahead) and extended instructions (5% ahead), making it suitable for specific algorithm-heavy tasks. However, for systems that need more PCIe connectivity, the 6511P's 136 lanes versus 88 lanes is a decisive factor, as it allows for more GPUs, NVMe drives, or network adapters.

For most server deployments, the 6511P is the superior choice based on benchmark performance. The 6515P has niche advantages but cannot match the 6511P's overall throughput.

Specification Differences

| Specification | Intel Xeon 6511P | Intel Xeon 6515P |

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

| Boost Clock | 4.20 GHz | 3.80 GHz |

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

| Part Number | SRVU9 | SRVU6 |

| Launch MSRP | $815 | $740 |

| Average Benchmark Score | 71051 | 67006 |

| Percentile vs All CPUs | 94 | 93 |

| Wins in Head-to-Head | 12 | 5 |

All other specifications are identical: 16 cores, 32 threads, 2.30 GHz base clock, 150 W TDP, Intel Socket 4710, Granite Rapids architecture, 5 nm process node, 112 KB L1 per core, 2 MB L2 per core, 72 MB shared L3, DDR5 memory with eight-channel 409.6 GB/s bandwidth, ECC support, no integrated graphics, and a release date of 2025-02-23.