CPU Comparison

The Intel Core i7-950 and Intel Xeon W3550 are, on paper, nearly identical silicon. Both are 45 nm Bloomfield parts with 4 cores, 8 threads, 3.07 GHz base clocks, and 3.33 GHz boost clocks. The benchmark data confirms this kinship, but the differences in their intended market segments and feature sets define their distinct identities.

Head-to-Head Benchmarks

The head-to-head benchmark results show a striking pattern: the Core i7-950 wins every single test, yet the margins are so narrow that they border on statistical noise. In Cinebench R15 multi-core, the i7-950 scores 280 against the Xeon W3550's 279, a delta of just 0.4%. That is the largest margin in any test, and it represents a single point on a scale where both processors are firmly in the same performance tier.

Moving to Cinebench R20 multi-core, the i7-950 posts 1167 versus 1166 for the Xeon W3550, a 0.1% advantage. The R23 multi-core test tells the same story: 2780 for the i7-950 and 2778 for the Xeon, again a 0.1% gap. In single-core workloads, the two are perfectly matched. Both score 164 in Cinebench R20 single-core and 392 in Cinebench R23 single-core, with a delta of 0% in each case.

The aggregate numbers reinforce this near-identical performance profile. The i7-950 carries an average benchmark score of 957, while the Xeon W3550 sits at 956. The delta between them is 0.1%, and both land in the 26th percentile of all CPUs. The i7-950's nearest rival list includes the Xeon W3550 at a 0.1% delta, and the Xeon's list includes the i7-950 at -0.1%. These are the closest possible comparisons; the data shows two chips that are effectively interchangeable in raw compute performance.

It is importantly the i7-950 wins all five head-to-head matchups, but the practical significance of a 0.1% to 0.4% lead in any workload is negligible. These deltas fall well within run-to-run variance for any benchmark suite. The decisive factor between these two parts is not speed, it is platform features and target use case.

FAQ

Q: Which processor is faster in multi-core workloads?

A: The Intel Core i7-950 holds a marginal lead in every multi-core test. It scores 280 versus 279 in Cinebench R15, 1167 versus 1166 in R20, and 2780 versus 2778 in R23. The largest delta is 0.4% in R15; the other two are 0.1%.

Q: Are there any single-core performance differences?

A: No. Both processors score exactly 164 in Cinebench R20 single-core and 392 in Cinebench R23 single-core. The head-to-head delta for both tests is 0%.

Q: Do the two processors share the same underlying architecture?

A: Yes. Both are built on Intel's Nehalem architecture with the Bloomfield codename. They use the same 45 nm process node, contain 731 million transistors, and have a die size of 263 mm².

Q: What is the difference in their cache configurations?

A: There is no difference. Both feature 64 KB of L1 cache per core, 256 KB of L2 cache per core, and 8 MB of shared L3 cache.

Q: How do they compare in overall benchmark percentile?

A: They are statistically identical. The Core i7-950 is in the 26th percentile of all CPUs with an average benchmark score of 957; the Xeon W3550 is also in the 26th percentile with an average score of 956.

Q: Which processor has a higher average benchmark score?

A: The Core i7-950 leads with an average score of 957, versus 956 for the Xeon W3550. This 1-point difference represents a 0.1% delta.

The Verdict

The data presents a clear conclusion: performance is not a differentiator between these two processors. The Core i7-950 wins every benchmark in the head-to-head comparison, but the margins are 0.4% or less. The average benchmark scores differ by 1 point out of roughly 957. Any user selecting between these two based purely on compute speed would be choosing between two identical performers.

The decision rests entirely on platform requirements. The Xeon W3550 supports ECC memory, a feature the Core i7-950 lacks. This makes the Xeon the only choice for workstation or server builds where memory error correction is a non-negotiable requirement. The Core i7-950 is positioned as a desktop part, while the Xeon W3550 targets the server and workstation segment. Both are end-of-life products, so availability and platform compatibility with existing Intel Socket 1366 motherboards will drive most real-world decisions.

For a general-purpose desktop system where ECC is not required, the Core i7-950's negligible benchmark lead gives it a nominal edge. For any reliability-focused workstation deployment, the Xeon W3550's ECC support makes it the functionally superior option, despite the 0.1% average score deficit.

Specification Differences

The two processors share the vast majority of their specifications. Both have 4 cores, 8 threads, a 3.07 GHz base clock, a 3.33 GHz boost clock, a 130 W TDP, and use the Intel Socket 1366. Both support DDR3 memory with a triple-channel memory bus and PCIe Gen 2. Neither has integrated graphics, and neither has an unlocked multiplier.

The differences are concentrated in a few fields. The Core i7-950 is classified under the "Core i7 (Bloomfield)" generation, while the Xeon W3550 falls under "Xeon (Bloomfield)". The market segment differs: the i7-950 is a Desktop part, whereas the Xeon W3550 is aimed at Server/Workstation. The most functionally significant difference is ECC memory support, the i7-950 does not support it, while the Xeon W3550 does. The part numbers also differ, with the i7-950 carrying SLBEN and the Xeon W3550 carrying SLBEY.

Architecture Differences

From an architecture standpoint, these are the same chip. Both use Intel's Nehalem architecture with the Bloomfield codename. The process node is identical at 45 nm, produced by Intel's own foundry. Both integrate 731 million transistors on a 263 mm² die.

The cache hierarchy is a mirror image: 64 KB of L1 per core, 256 KB of L2 per core, and 8 MB of shared L3. Memory support is DDR3 with a triple-channel bus on both parts. PCIe connectivity is Gen 2 for each.

The only architectural distinction is the ECC memory controller present on the Xeon W3550, which is a feature of the memory path rather than the core design. This single feature, enabled by the Xeon's server-oriented binning, separates what is otherwise identical silicon. The release dates differ, the i7-950 launched in June 2009, while the Xeon W3550 arrived in August 2009, but the underlying architecture remained unchanged between those two months. The Xeon's ECC capability is the sole architectural trait that gives it a different functional role in a system.