Intel Xeon E5405

The Intel Xeon E5405 is a 4-core, 4-thread server processor from the Harpertown generation, built on Intel's 45 nm process. With a base clock of 2000.00 MHz and an 80 W TDP, this end-of-life part targets the Server/Workstation segment, offering dual-die L2 caching and ECC memory support. Its benchmark profile places it in the 9th percentile of all CPUs, with an average score of 513, indicating that it sits firmly in the entry-level tier of its era.

How It Compares

Against the Intel Core i7-720QM, the E5405 is virtually tied, with a deltaPct of 0.3% in favor of the Xeon. The average scores of 513 versus 512 are within run-to-run noise, meaning the two processors deliver nearly identical aggregate performance. This parity is notable because the i7-720QM is a mobile quad-core part, while the E5405 is a server chip; the data shows that generation and platform matter less than raw core count and clock in this performance class.

The AMD Phenom II X3 B75 edges out the E5405 by 0.5%, with a score of 515 versus 513. This is a three-core AMD part beating a four-core Intel server chip, which suggests the Phenom's higher per-core efficiency compensates for its missing fourth core. The delta is small enough to be considered a statistical tie, but the direction is consistent: the E5405 does not lead this comparison.

The Intel Core i3-3110M posts a score of 517, which is 0.7% higher than the E5405's 513. This is a dual-core, four-thread mobile processor from a much later generation, yet it outperforms the older quad-core Xeon. The data indicates that architectural improvements across generations have a greater impact on average scores than simply adding more physical cores.

The Intel Xeon L5408 achieves a 517 average score, leading the E5405 by 0.8%. Both are Harpertown-generation Xeons, but the L5408 is a low-power variant. The performance gap, while tiny, suggests that the L5408's binning or power characteristics translate into a marginal benchmark advantage, making it the stronger choice within the same family.

Single-Thread vs Multi-Thread Behavior

The E5405's single-thread scores are disproportionately low relative to its multi-thread results. In Cinebench R20, the single-core score is 88, while the multi-core score is 625 — a ratio of approximately 7.1x. This is a very wide gap, indicating that the processor scales well across its four physical cores but struggles with per-thread instruction throughput.

For real workloads, this split means the E5405 is acceptable for parallel tasks like video rendering or batch processing, where all cores can be utilized simultaneously. However, single-threaded applications — such as legacy database queries, spreadsheet operations, or lightly threaded scripting — will see performance that is severely limited by the 2000.00 MHz base clock and the Core 2 architecture's modest IPC.

In Cinebench R23, the single-core score of 210 versus a multi-core score of 1490 shows a similar pattern, with a roughly 7.1x scaling factor. This consistency across different benchmark versions reinforces that the E5405's strength lies in throughput, not responsiveness. Users should expect sluggish behavior in interactive or latency-sensitive tasks, while batch jobs that are core-count-bound will fare much better.

The lack of a boost clock — the field is null — means the E5405 cannot dynamically increase its frequency under load. This locks the processor to 2000.00 MHz at all times, which explains why single-thread results are so far behind modern parts that can boost well above their base clocks.

Power and Thermals

The E5405 carries a TDP of 80 W, which places it in a moderate power envelope for a quad-core server processor of its generation. This is not an extreme power draw, but it is also not a low-power part; the existence of the L5408 sibling — which scores higher on average at 517 — suggests that lower-power variants of the same architecture can achieve better results.

The 45 nm process node and dual-die design, with each die measuring 107 mm² and containing 6 MB of L2 cache, contribute to the thermal profile. The processor contains 820 million transistors across two dies, and the 80 W TDP implies that a capable air cooler designed for Socket 771 would be sufficient for most server chassis. The absence of an integrated GPU means all thermal headroom is dedicated to CPU cores, which simplifies cooling requirements.

Given the end-of-life status, thermals are mostly a historical consideration. The 80 W class suggests that standard 1U or 2U server heatsinks from that era were adequate, and the dual-die layout means heat is spread across two physical packages rather than concentrated in one hotspot. For modern use, an aftermarket cooler compatible with Socket 771 would manage this processor without difficulty.

FAQ

Q: What is the average benchmark score of the Intel Xeon E5405?

A: The average benchmark score is 513, placing it in the 9th percentile of all CPUs.

Q: How does the E5405 compare to the Intel Core i7-720QM?

A: The E5405 scores 513, which is 0.3% higher than the i7-720QM's 512, making them effectively tied.

Q: What is the processor's launch MSRP?

A: The launch MSRP was $209.

Q: Does the E5405 support ECC memory?

A: Yes, ECC memory is supported, with dual-channel DDR2 or DDR3 depending on the motherboard.

Q: What is the multi-core Cinebench R23 score?

A: The Cinebench R23 multi-core score is 1490, while the single-core score is 210.

Q: What socket does the E5405 use?

A: It uses Intel Socket 771, and the processor is based on the Core 2 architecture with the Harpertown codename.

Benchmark Performance

The E5405's benchmark results are tightly clustered with its nearest rivals, but the direction of the deltas reveals a consistent pattern. In Cinebench R15 multi-core, the score is 150, which is a modest absolute number but aligns with the average score of 513 across all tests. The R20 multi-core score of 625 and R23 multi-core score of 1490 show progressive scaling across benchmark versions, though these numbers are low by modern standards.

The single-core results are more revealing. In R20, the score of 88 is severely constrained, and in R23, the score of 210 is similarly low. These figures explain why the E5405 sits at the 9th percentile — the processor's per-thread performance is its primary weakness. The multi-core-to-single-core ratio of roughly 7.1x in both R20 and R23 indicates that scaling is linear but the baseline is very low.

Comparing to rivals, the E5405's 513 average score is 0.3% above the i7-720QM's 512, 0.5% below the Phenom II X3 B75's 515, 0.7% below the i3-3110M's 517, and 0.8% below the Xeon L5408's 517. These deltas are all within 1%, which means the E5405 is statistically indistinguishable from its competitors in aggregate performance. However, the fact that every rival except the i7-720QM scores higher suggests that the E5405 is at the low end of its peer group.

The Cinebench R23 multi-core score of 1490 is particularly telling when compared to the average score of 513. The R23 test is more demanding, and the E5405's ratio of multi-core to average score (1490/513 ≈ 2.9x) indicates that the processor performs relatively better in multi-threaded workloads than in the mixed benchmark suite. This is consistent with a quad-core design that lacks single-thread efficiency.

In absolute terms, the E5405's scores are all below 1500 in the most recent Cinebench version, which places it firmly in legacy territory. The 45 nm process, 820 million transistors, and dual-die layout with 6 MB of L2 per die are architectural factors that cap performance. The lack of a boost clock and the fixed 2000.00 MHz frequency further limit the processor, as there is no headroom for transient performance increases.

The data shows a processor that was designed for parallel server workloads where core count matters more than clock speed. Its benchmark profile reflects this: multi-threaded scores are proportionally higher than single-threaded ones, and its aggregate performance is within 1% of its closest competitors. For any modern application, the E5405 is outclassed, but within its historical context, it delivers consistent, if unspectacular, throughput.