Intel Core i7-4940MX vs Intel Xeon E3-1545M v5 Comparison

The Intel Core i7-4940MX and the Intel Xeon E3-1545M v5 are both end-of-life mobile processors with 4 cores and 8 threads, but they target entirely different use cases. The i7-4940MX is a Haswell-era Extreme Edition chip with an unlocked multiplier, while the Xeon E3-1545M v5 is a Skylake-H server/workstation part with ECC memory support. Benchmark results show a clear and consistent advantage for the Xeon in every single test, making the choice straightforward for most builders, though the i7’s overclocking capability and lower average benchmark score tell a more nuanced story than the raw numbers alone.

Where Each One Wins

The data is unambiguous: the Intel Xeon E3-1545M v5 wins all six head-to-head benchmark comparisons. There is no test in the FACT PACK where the Intel Core i7-4940MX comes out ahead. The Xeon’s winning margin is consistent, ranging from 11.3% to 12% across all Cinebench R15, R20, and R23 multi-core and single-core tests. This means that for any workload that relies on raw CPU throughput, whether single-threaded or multi-threaded, the Xeon is the superior choice.

The Core i7-4940MX does have one unique advantage: its multiplier is unlocked. This feature allows for overclocking, which could potentially close the performance gap in real-world usage, but the FACT PACK provides no benchmark data to support this. In strictly stock configurations, the Xeon wins every measurable category. The i7-4940MX does post a slightly higher average benchmark score of 1886 compared to the Xeon’s 1879, but this is a negligible 0.4% difference and is not reflected in any head-to-head test. That average score is likely pulled up by its Geekbench results (3869 multi-core, 1227 single-core), which are not part of the head-to-head comparisons. When the tests are directly compared, the Xeon’s victory is total.

Architecture Differences

The two CPUs are separated by two generations of Intel architecture. The Core i7-4940MX is built on the Haswell architecture using a 22 nm process node, while the Xeon E3-1545M v5 uses the newer Skylake architecture on a 14 nm process node. This process shrink is significant: the Xeon packs 2,300 million transistors on a 171 mm² die, compared to the i7’s 1,400 million transistors on a slightly larger 177 mm² die. The smaller, denser process node is a key reason the Xeon achieves higher performance while consuming less power.

The Xeon’s 45 W TDP is notably lower than the i7’s 57 W TDP, despite the Xeon having more transistors. This efficiency gain is directly attributable to the 14 nm process. Both CPUs share the same cache hierarchy: 64 KB of L1 per core, 256 KB of L2 per core, and 8 MB of shared L3 cache. Memory support differs substantially. The i7-4940MX supports only DDR3 memory with a dual-channel bus and a maximum bandwidth of 25.6 GB/s. The Xeon E3-1545M v5 supports both DDR3 and DDR4, also on a dual-channel bus, but with a higher maximum bandwidth of 34.1 GB/s. The Xeon is also the only one of the two to support ECC memory, a critical feature for workstation and server reliability.

The integrated graphics differ as well, with the i7 featuring the Intel HD 4600 and the Xeon equipped with the Iris Pro Graphics P580. The Xeon is classified as a server/workstation part on the Intel BGA 1440 socket, while the i7 is a mobile part on Intel Socket G3. The i7 was released in January 2014 with a launch MSRP of $1096, while the Xeon launched in January 2016 with a launch MSRP of $679.

Head-to-Head Benchmarks

The Xeon E3-1545M v5 dominates every benchmark comparison, and the margins are remarkably consistent. In Cinebench R15 multi-core, the Xeon scores 654 against the i7’s 580, a difference of 11.3%. The single-core test shows a similar gap: 92 versus 81, a 12% advantage for the Xeon. This pattern holds across newer Cinebench versions. In Cinebench R20 multi-core, the Xeon scores 2728 versus the i7’s 2418, again an 11.4% difference. The single-core R20 result is 385 versus 341, also an 11.4% gap.

The most recent Cinebench R23 tests continue the trend. The Xeon posts 6497 in multi-core against the i7’s 5759, an 11.4% lead. In single-core R23, the Xeon scores 917 while the i7 manages 813, an 11.3% difference. The consistency of these margins across different benchmark versions is striking. It suggests the performance gap is structural, not workload-dependent. The Xeon’s newer architecture and higher memory bandwidth likely contribute to this uniform advantage. The i7’s higher base clock of 3.10 GHz and boost clock of 4.00 GHz are not enough to overcome the Xeon’s architectural efficiency, even though the Xeon runs at lower clocks of 2.90 GHz base and 3.80 GHz boost.

Geekbench scores are only available for the i7-4940MX, which scores 3869 multi-core and 1227 single-core. Without comparable Xeon data, these numbers are useful only for context regarding the i7’s overall performance level, which places it in the 43rd percentile of all CPUs. The Xeon also sits in the 43rd percentile, indicating that despite the Xeon’s head-to-head victories, both processors are in the same overall performance tier when compared to the broader CPU landscape.

The Verdict

The data makes a clear recommendation: choose the Intel Xeon E3-1545M v5 for any application where performance is the sole criterion. It wins every benchmark in the FACT PACK by margins of at least 11.3%, and it does so while consuming less power (45 W TDP versus 57 W) and supporting more modern memory (DDR3 and DDR4 versus DDR3 only). The Xeon also supports ECC memory, which is essential for error-correcting workloads in workstation or server environments. Its integrated Iris Pro Graphics P580 is likely more capable than the i7’s HD 4600, though no benchmark data is provided to confirm this.

The Intel Core i7-4940MX is the choice only if the unlocked multiplier is a decisive factor. Overclocking the 4.00 GHz boost clock could theoretically narrow or reverse the performance gap, but the FACT PACK provides no overclocked benchmark results to validate this. In stock form, the i7 is slower in every measurable way. Its higher average benchmark score of 1886 versus the Xeon’s 1879 is a statistical artifact of the different benchmark sets, not evidence of superiority. The i7’s higher launch MSRP of $1096, compared to the Xeon’s $679, further reinforces that the Xeon is the better-performing and more efficiently priced part, though pricing should not be a primary consideration in this analysis. For a builder who needs maximum performance out of the box and can use ECC memory, the Xeon is the clear winner. For a builder who prioritizes overclocking headroom and does not need ECC, the i7-4940MX remains a viable, if slower, option.

FAQ

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

A: The Intel Xeon E3-1545M v5 is faster in every multi-core test. It scores 654 versus 580 in Cinebench R15, 2728 versus 2418 in R20, and 6497 versus 5759 in R23, representing an 11.4% advantage in each case.

Q: Does the Core i7-4940MX win any benchmark?

A: No. The FACT PACK shows the Xeon E3-1545M v5 winning all six head-to-head tests. The i7-4940MX has zero wins in the comparisons provided.

Q: What is the difference in memory bandwidth?

A: The Xeon E3-1545M v5 supports a maximum memory bandwidth of 34.1 GB/s, while the Core i7-4940MX is limited to 25.6 GB/s. The Xeon also supports both DDR3 and DDR4, whereas the i7 only supports DDR3.

Q: Does either CPU support ECC memory?

A: Only the Intel Xeon E3-1545M v5 supports ECC memory. The Core i7-4940MX does not have ECC support.

Q: How do their TDPs compare?

A: The Xeon E3-1545M v5 has a TDP of 45 W, which is lower than the Core i7-4940MX’s 57 W TDP. This makes the Xeon more power-efficient despite its higher performance.

Q: Are the cache sizes the same?

A: Yes. Both CPUs have 64 KB of L1 cache per core, 256 KB of L2 cache per core, and 8 MB of shared L3 cache.

Specification Differences

| Specification | Intel Core i7-4940MX | Intel Xeon E3-1545M v5 |

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

| Base Clock | 3.10 GHz | 2.90 GHz |

| Boost Clock | 4.00 GHz | 3.80 GHz |

| TDP | 57 W | 45 W |

| Socket | Intel Socket G3 | Intel BGA 1440 |

| Architecture | Haswell | Skylake |

| Process Node | 22 nm | 14 nm |

| Transistors | 1,400 million | 2,300 million |

| Die Size | 177 mm² | 171 mm² |

| Memory Support | DDR3 | DDR3, DDR4 |

| Memory Bandwidth | 25.6 GB/s | 34.1 GB/s |

| ECC Memory | No | Yes |

| Integrated Graphics | Intel HD 4600 | Iris Pro Graphics P580 |

| Market Segment | Mobile | Server/Workstation |

| Release Date | 2014-01-19 | 2016-01-23 |

| Launch MSRP | $1096 | $679 |

| Multiplier Unlocked | Yes | No |

| Part Number | SR1PP | SR2QU |