Intel Core i9-7900X vs Intel Xeon W-2155 Comparison

The Intel Core i9-7900X and the Intel Xeon W-2155 are nearly identical in core architecture and raw performance, but the data clearly separates them by platform purpose. The i9-7900X wins all six head-to-head benchmark comparisons, though by margins of less than one percent. The Xeon W-2155 counters with ECC memory support, more PCIe lanes, and a locked multiplier, making it the workstation-oriented choice. For pure compute speed, the i9-7900X is the pick; for stability and server-grade features, the Xeon W-2155 justifies its position despite trailing in every benchmark.

The Verdict

Benchmark results show the Core i9-7900X as the faster processor in every tested workload, but the differences are marginal. The largest gap appears in Cinebench R20 single-core, where the i9-7900X leads by 0.9%. All other tests show a 0.8% advantage for the i9-7900X. In practical terms, this means the i9-7900X delivers a consistent, though tiny, performance edge across both single-threaded and multi-threaded tasks.

The Xeon W-2155 is not a performance competitor here; it is a feature competitor. Its 48 PCIe Gen 3 lanes (CPU only) surpass the i9-7900X’s 44 lanes, and it supports ECC memory, which the i9-7900X does not. The Xeon also has a locked multiplier, whereas the i9-7900X is unlocked for overclocking. Users who need ECC for data integrity in workstations should choose the Xeon W-2155, accepting a sub-1% performance penalty. Users who prioritize maximum speed and overclocking flexibility should select the i9-7900X, which holds a 0.8-0.9% lead in all benchmarks.

Both processors sit at the 60th percentile among all CPUs, with average benchmark scores of 5120 (i9-7900X) and 5072 (Xeon W-2155). The i9-7900X’s nearest rival is the AMD EPYC 7262, which scores 5109 and trails by only 0.2%. The Xeon W-2155’s closest competitor is the AMD Ryzen 7 PRO 5750GE, with a 0% delta. This places both Intel parts in a tight performance cluster, where the Xeon W-2155 is effectively tied with several other CPUs.

Architecture Differences

Both processors are built on Intel’s 14 nm process and share the Skylake architecture, with the i9-7900X using the Skylake-X codename and the Xeon W-2155 using Skylake-W. Both have 10 cores and 20 threads, with identical base clocks of 3.30 GHz and boost clocks of 4.50 GHz. The TDP is 140 watts for both, and they share the same Intel Socket 2066.

The differences lie in cache and platform features. The i9-7900X has 14 MB of shared L3 cache, while the Xeon W-2155 has 13.75 MB. Both have 64 KB of L1 cache per core and 1 MB of L2 cache per core. The Xeon W-2155’s die size is listed at 484 mm², a detail not provided for the i9-7900X.

Memory support is identical in bandwidth: both use DDR4 with a quad-channel memory bus and 85.3 GB/s of bandwidth. The critical split is ECC memory support, which is present on the Xeon W-2155 but absent on the i9-7900X. PCIe connectivity also differs: the Xeon W-2155 offers 48 Gen 3 lanes (CPU only), while the i9-7900X offers 44 lanes. The i9-7900X has an unlocked multiplier, enabling overclocking, while the Xeon W-2155 is locked.

Head-to-Head Benchmarks

The i9-7900X wins all six head-to-head comparisons, but the margins are remarkably consistent. In Cinebench R15 multicore, the i9-7900X scores 1782 against the Xeon W-2155’s 1767, a 0.8% lead. The single-core R15 test shows 251 versus 249, also a 0.8% advantage. Moving to Cinebench R20, the multicore result is 7425 versus 7365 (0.8%), and the single-core result is 1048 versus 1039 (0.9%). In Cinebench R23, the multicore score is 17680 versus 17538 (0.8%), and the single-core score is 2496 versus 2475 (0.8%).

The pattern is clear: the i9-7900X’s advantage is real but narrow, hovering just under one percent across every test. The largest absolute gap is in Cinebench R23 multicore, where the i9-7900X leads by 142 points. The smallest absolute gap is in Cinebench R15 single-core, where the difference is only 2 points. Notably, the Geekbench results are only available for the i9-7900X (8841 multicore, 1437 single-core), with no corresponding Xeon W-2155 scores in the data.

Given the consistent 0.8-0.9% margins, the benchmark data suggests that the two processors are architecturally equivalent in compute capability, with the i9-7900X enjoying a slight clock-for-clock or cache-related edge. The 0.25 MB difference in L3 cache (14 MB vs 13.75 MB) likely contributes to the i9-7900X’s narrow wins, though the effect is minimal.

FAQ

Q: Which processor has better multi-core performance?

A: The Intel Core i9-7900X wins all multi-core benchmarks, including Cinebench R23 (17680 vs 17538) and Cinebench R20 (7425 vs 7365), with a 0.8% advantage in each case.

Q: Does the Xeon W-2155 support ECC memory?

A: Yes, the Xeon W-2155 supports ECC memory, while the Core i9-7900X does not. This is a key differentiator for workstation reliability.

Q: Are the clock speeds identical between the two?

A: Yes, both processors have a base clock of 3.30 GHz and a boost clock of 4.50 GHz, with the same 140-watt TDP.

Q: Can the Core i9-7900X be overclocked?

A: Yes, the i9-7900X has an unlocked multiplier, while the Xeon W-2155’s multiplier is locked.

Q: How many PCIe lanes does each processor provide?

A: The Xeon W-2155 provides 48 Gen 3 lanes (CPU only), while the Core i9-7900X provides 44 Gen 3 lanes (CPU only).

Q: What is the average benchmark score difference?

A: The i9-7900X has an average benchmark score of 5120, while the Xeon W-2155 scores 5072, a difference of 0.9% that aligns with the individual test margins.

Where Each One Wins

The Core i9-7900X wins every benchmark test included in the data, making it the clear choice for raw compute performance. Its 0.8% lead in Cinebench R15, R20, and R23 multicore tests, plus its 0.8-0.9% lead in single-core tests, means it consistently outperforms the Xeon W-2155 in both threaded and single-threaded workloads. For users running CPU-bound tasks like rendering, compilation, or scientific simulations, the i9-7900X delivers a measurable, if small, speed advantage. Its unlocked multiplier also gives overclockers headroom to extend that lead further, a feature the Xeon W-2155 lacks entirely.

The Xeon W-2155 wins in platform features rather than benchmarks. Its 48 PCIe Gen 3 lanes enable more expansion cards, GPUs, or NVMe drives compared to the i9-7900X’s 44 lanes. ECC memory support is the standout advantage, offering error correction for mission-critical data processing where a single-bit error is unacceptable. The locked multiplier is a drawback for enthusiasts, but for a workstation that must run 24/7 at stable clocks, this is often desirable. The Xeon’s larger die size (484 mm²) suggests a more robust physical design, though this does not translate into higher benchmark scores.

In summary, the i9-7900X wins on performance across the board, while the Xeon W-2155 wins on reliability features. The choice hinges on whether benchmark speed or platform robustness matters more. The data shows a 0.8-0.9% performance gap, which is negligible for most applications, making the Xeon W-2155 a compelling option for those who need ECC and extra PCIe lanes.

Specification Differences

| Specification | Intel Core i9-7900X | Intel Xeon W-2155 |

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

| Codename | Skylake-X | Skylake-W |

| Generation | Core i9 (X-Series 7th Gen) | Xeon W (Skylake-W) |

| L3 Cache | 14 MB (shared) | 13.75 MB (shared) |

| ECC Memory | false | true |

| PCIe Lanes | Gen 3, 44 Lanes (CPU only) | Gen 3, 48 Lanes (CPU only) |

| Market Segment | Desktop | Server/Workstation |

| Release Date | 2017-06-25 | 2017-08-28 |

| Launch MSRP | $999 | $1440 |

| Multiplier Unlocked | true | false |

| Part Number | SR3L2 | SR3LR |

| Die Size | not listed | 484 mm² |

All other core specifications are identical: 10 cores, 20 threads, 3.30 GHz base clock, 4.50 GHz boost clock, 140 W TDP, Intel Socket 2066, 14 nm process, Skylake architecture, DDR4 memory, quad-channel bus, 85.3 GB/s bandwidth, 64 KB L1 cache per core, and 1 MB L2 cache per core. Neither processor has integrated graphics. Both are end-of-life products.