CPU Comparison

The Intel Xeon W3540 and Intel Core i7-940 are near-identical silicon, sharing the same Nehalem architecture, Bloomfield codename, 45 nm process node, and a 130 W TDP. Both feature 4 cores and 8 threads, with identical base and boost clocks of 2.93 GHz and 3.20 GHz respectively. The data reveals a consistent, albeit narrow, performance advantage for the Xeon part across every benchmark recorded, making the comparison less about raw capability and more about platform positioning and feature sets.

Head-to-Head Benchmarks

The benchmark results show a clean sweep for the Intel Xeon W3540, though the margins are remarkably tight. In the Cinebench R15 multi-core test, the Xeon scores 267 against the Core i7-940’s 264, a difference of 1.1%. This pattern continues in Cinebench R20 multi-core, where the Xeon posts 1113 versus 1102 for the i7-940, a 1% lead. The single-core results tell a similar story, with the Xeon achieving 157 in Cinebench R20 single-core compared to 155 for the i7-940, a 1.3% advantage.

The most substantial gap appears in the Cinebench R23 single-core run, where the Xeon’s 374-point score outpaces the i7-940’s 370 by 1.1%. Meanwhile, the Cinebench R23 multi-core result sees the Xeon at 2652, ahead of the i7-940’s 2626 by 1%. The data shows a total of 5 wins for the Xeon W3540 and 0 for the Core i7-940 in their head-to-head matchups.

These deltas are small, but they are uniform across every workload. The average benchmark scores reflect this: the Xeon W3540 sits at 913 average, while the Core i7-940 averages 903. Interestingly, the Xeon’s nearest rival is the Intel Pentium Gold G6405T with an average score of 915, a -0.2% delta, while the Core i7-940’s closest competitor is the Intel Core i5-5350U, which matches its 903 average exactly. Both processors land in the 24th percentile of all CPUs, indicating that despite their age, they perform at a comparable level to much newer low-end parts. The question the data raises is whether the Xeon’s consistent edge is meaningful enough to justify its server-oriented positioning.

FAQ

Q: Which processor has a higher multi-core performance?

A: The Intel Xeon W3540 leads in all multi-core tests. It scores 267 versus 264 in Cinebench R15, 1113 versus 1102 in R20, and 2652 versus 2626 in R23 multi-core.

Q: Is there any benchmark where the Core i7-940 wins?

A: No. The head-to-head data records 5 wins for the Intel Xeon W3540 and 0 wins for the Intel Core i7-940 across all five Cinebench tests.

Q: How do these processors compare in single-core performance?

A: The Xeon W3540 holds a slight edge. It scores 157 versus 155 in Cinebench R20 single-core (a 1.3% delta) and 374 versus 370 in Cinebench R23 single-core (a 1.1% delta).

Q: Do the two processors share the same specifications?

A: Yes, for the most part. Both have 4 cores, 8 threads, identical clock speeds, the same cache layout, and the same 45 nm process node. They differ in market segment, ECC memory support, and part number.

Q: What is the performance gap between the two processors?

A: The largest delta is 1.3% in Cinebench R20 single-core. The smallest is 1% in Cinebench R20 multi-core and Cinebench R23 multi-core. All differences favor the Xeon W3540.

Q: How do these chips compare to modern low-end processors?

A: Both sit at the 24th percentile of all CPUs. The Xeon W3540’s average score of 913 places it near the AMD Ryzen 3 3250U (908, 0.5% delta), while the Core i7-940’s 903 average is matched exactly by the Intel Core i5-5350U.

Architecture Differences

The architectural core of both processors is identical, built on Intel’s Nehalem architecture with the Bloomfield codename. They share the same 45 nm process node, fabricated by Intel with 731 million transistors on a 263 mm² die. The cache hierarchy is also the same: 64 KB of L1 per core, 256 KB of L2 per core, and 8 MB of shared L3 cache. Memory support is DDR3 with a triple-channel bus, and both use PCIe Gen 2. The socket is Intel Socket 1366 for both.

The meaningful divergence lies in their intended platform roles. The Xeon W3540 is marked for the Server/Workstation segment, while the Core i7-940 is a Desktop part. This positioning manifests in one critical feature: ECC memory support. The Xeon W3540 supports ECC memory, whereas the Core i7-940 does not. This is the only functional difference in the feature set that would affect system design and reliability considerations. The generation field also differs, with the Xeon labeled as "Xeon (Bloomfield)" and the Core i7 as "Core i7 (Bloomfield)," though this is a branding distinction rather than a technical one. The part numbers diverge as well: SLBEX for the Xeon and SLBCK for the Core i7.

The lack of integrated graphics on both parts is notable, but expected for this era and platform. The production status is end-of-life for both, and neither has an unlocked multiplier. The release dates are close but not identical, with the Core i7-940 arriving on 2008-11-16 and the Xeon W3540 later on 2009-03-29. The data suggests these are the same die with different validation and feature enablement, rather than fundamentally different designs.

The Verdict

From the data alone, the Intel Xeon W3540 is the superior processor in every measured benchmark. It wins all five head-to-head tests, with deltas ranging from 1% to 1.3%. Its average benchmark score of 913 is 10 points higher than the Core i7-940’s 903. If raw performance is the sole criterion, the Xeon W3540 is the clear choice.

However, the significance of this performance advantage must be weighed against the platform context. The Xeon W3540’s ECC memory support is a meaningful feature for server and workstation environments where data integrity is paramount. The Core i7-940, lacking ECC support, is suited for desktop use where such reliability features are less critical. For a desktop user, the 1% to 1.3% performance delta is negligible in real-world terms. The data shows both processors are functionally equivalent in core architecture, clocks, and cache, so the choice hinges on whether the user needs ECC memory and is building a workstation/server versus a standard desktop.

The percentile ranking of 24 for both CPUs indicates they offer similar overall performance relative to the broader market. The Xeon’s nearest rivals include the AMD Athlon Silver 3050U (917, -0.5% delta) and the Intel Pentium Gold G6405T (915, -0.2% delta), while the Core i7-940 sits alongside the Intel Core i5-5350U and AMD A10-7860K. This suggests that in a modern context, neither chip is a performance powerhouse, but the Xeon’s consistent, if small, lead makes it the better option for workloads that can leverage its ECC capability.

Specification Differences

The following specifications differ between the Intel Xeon W3540 and the Intel Core i7-940:

• Market Segment: The Xeon W3540 is targeted at Server/Workstation, while the Core i7-940 is a Desktop part.
• ECC Memory Support: The Xeon W3540 supports ECC memory; the Core i7-940 does not.
• Generation Label: The Xeon is listed as "Xeon (Bloomfield)," while the Core i7 is "Core i7 (Bloomfield)."
• Part Number: The Xeon W3540 uses part number SLBEX; the Core i7-940 uses SLBCK.
• Release Date: The Core i7-940 launched on 2008-11-16, while the Xeon W3540 followed on 2009-03-29.

All other core specifications are identical: 4 cores, 8 threads, 2.93 GHz base clock, 3.20 GHz boost clock, 130 W TDP, Intel Socket 1366, Nehalem architecture, Bloomfield codename, 45 nm process, 731 million transistors, 263 mm² die size, 64 KB L1 per core, 256 KB L2 per core, 8 MB shared L3, DDR3 memory support, triple-channel memory bus, PCIe Gen 2, no integrated graphics, end-of-life production status, and locked multiplier.

Where Each One Wins

The Intel Xeon W3540 wins in every benchmark category recorded. It takes the multi-core tests with scores of 267 (R15), 1113 (R20), and 2652 (R23), and the single-core tests with 157 (R20) and 374 (R23). The data does not show a single test where the Core i7-940 outperforms the Xeon. The Xeon’s edge is most pronounced in Cinebench R20 single-core, where it leads by 1.3%, and least in the multi-core tests, where the delta is 1%.

The use-case split is therefore not about performance, but about feature requirements. The Xeon W3540 is the appropriate choice for server or workstation builds where ECC memory support is required for error-correcting reliability in long-running or data-sensitive workloads. The Core i7-940, despite its identical performance profile, is suited for standard desktop builds where ECC is unnecessary. In practical terms, a user building a system with non-ECC DDR3 memory would see no meaningful difference between the two, as the 1% to 1.3% performance delta would be imperceptible in most applications. The Xeon’s advantage becomes relevant only when the platform demands ECC, making it the default pick for professional and enterprise environments, while the Core i7-940 remains a viable desktop alternative for users who do not need that capability.