Intel Core i7-4940MX vs Intel Xeon E3-1575M v5 Comparison

The Intel Xeon E3-1575M v5 and the Intel Core i7-4940MX are both high-end, end-of-life mobile processors from Intel, but they represent different architectural eras and market segments. The Xeon E3-1575M v5, a Skylake-H part from the Server/Workstation segment, and the Core i7-4940MX, a Haswell Extreme Edition mobile chip, share a core and thread count but diverge significantly in process technology, memory support, and benchmark performance. This analysis uses recorded database measurements to compare the two across several Cinebench workloads, highlighting where each processor holds an advantage, despite one winning every head-to-head test.

Where Each One Wins

The recorded data shows a clear sweep: the Intel Xeon E3-1575M v5 wins all six head-to-head benchmark comparisons against the Intel Core i7-4940MX. The Xeon’s victories span both multi-core and single-core tests across Cinebench R15, R20, and R23, making it the definitive performer in every measured category. The Core i7-4940MX records no wins in any of the six head-to-head benchmarks, so its strength lies not in raw Cinebench performance but in other characteristics captured in the database, such as its unlocked multiplier and lower launch MSRP.

For multi-threaded workloads, the Xeon E3-1575M v5 demonstrates a consistent advantage. In Cinebench R23 multi-core, it scores 6607 against the i7-4940MX’s 5759, a 14.7% difference. Similarly, in Cinebench R20 multi-core, the Xeon reaches 2774 while the i7-4940MX scores 2418, again a 14.7% gap. The Cinebench R15 multi-core test shows the Xeon at 665 versus 580 for the i7-4940MX, with a 14.7% delta. This pattern indicates that the Xeon’s architectural improvements, likely tied to its newer Skylake design and 14 nm process, translate directly into better sustained multi-core output.

Single-core performance also favors the Xeon E3-1575M v5, though the margins are nearly identical to the multi-core deltas. In Cinebench R23 single-core, the Xeon scores 932 versus 813 for the i7-4940MX, a 14.6% advantage. Cinebench R20 single-core shows 391 against 341, a 14.7% delta, and Cinebench R15 single-core records 93 versus 81, a 14.8% lead. These results suggest that the Xeon’s per-core efficiency, not just its multi-core scaling, outpaces the older Haswell design.

The Core i7-4940MX does have one unique capability in the database: it is multiplier-unlocked, whereas the Xeon E3-1575M v5 is not. This means the i7-4940MX allows for overclocking, a feature absent from the Xeon. For users who prioritize manual tuning, this could be a deciding factor, but the stock benchmark data does not reflect any overclocked performance. The i7-4940MX also carries a lower launch MSRP of $1096 compared to the Xeon’s $1207, though pricing is not a performance metric.

Architecture Differences

The two processors come from different Intel microarchitectures and manufacturing nodes. The Xeon E3-1575M v5 is built on Skylake-H, using a 14 nm process with 2,300 million transistors on a 171 mm² die. The Core i7-4940MX is a Haswell part, fabricated on a 22 nm process with 1,400 million transistors on a slightly larger 177 mm² die. The smaller process node for the Xeon allows for higher transistor density despite the larger transistor count, which contributes to its performance edge.

Both processors feature 4 cores and 8 threads, and they share identical cache hierarchies: 64 KB of L1 per core, 256 KB of L2 per core, and 8 MB of shared L3 cache. This means the architectural differences do not stem from cache capacity but from the underlying core design and process improvements. The Xeon’s Skylake architecture introduces efficiency gains over Haswell, which are visible in the consistent benchmark deltas.

Memory support differs notably. The Xeon E3-1575M v5 supports both DDR3 and DDR4 memory in a dual-channel configuration, with a memory bandwidth of 34.1 GB/s. The Core i7-4940MX supports only DDR3, also dual-channel, with a lower memory bandwidth of 25.6 GB/s. This 8.5 GB/s gap in theoretical bandwidth could affect memory-intensive workloads, though the database does not include such tests. The Xeon also supports ECC memory, while the i7-4940MX does not, aligning with its Server/Workstation market segment.

Integrated graphics separate the two as well. The Xeon E3-1575M v5 includes Iris Pro Graphics P580, while the Core i7-4940MX features Intel HD 4600. The database does not provide graphics benchmark scores, so no performance comparison is possible, but the Xeon’s higher-tier integrated graphics is a noted feature difference. The Xeon uses an Intel BGA 1440 socket, whereas the i7-4940MX uses Intel Socket G3, meaning they are not interchangeable in a system.

The Xeon’s release date is recorded as 2016-01-23, while the i7-4940MX came earlier, on 2014-01-19. Both are end-of-life products. The Xeon’s part number is SR2QV, and the i7-4940MX’s is SR1PP. The Xeon has a base clock of 3.00 GHz and a boost clock of 3.90 GHz, while the i7-4940MX has a slightly higher base clock of 3.10 GHz and a boost clock of 4.00 GHz. Despite the i7-4940MX’s higher clocks, the Xeon still wins all benchmarks, underscoring the IPC advantage of Skylake over Haswell.

Head-to-Head Benchmarks

The head-to-head data from the database lists six Cinebench tests, and the Intel Xeon E3-1575M v5 wins every one. The largest single delta is 14.8% in Cinebench R15 single-core, where the Xeon scores 93 and the i7-4940MX scores 81. The smallest delta is 14.6% in Cinebench R23 single-core, with scores of 932 and 813. All other tests show a delta of 14.7%, creating a remarkably uniform performance gap.

In Cinebench R15 multi-core, the Xeon scores 665, beating the i7-4940MX’s 580 by 14.7%. This test is often used to gauge rendering performance, and the Xeon’s lead indicates better multi-threaded efficiency. Cinebench R20 multi-core shows the Xeon at 2774 versus 2418, again 14.7% ahead. Cinebench R23 multi-core, the most recent workload, has the Xeon at 6607 and the i7-4940MX at 5759, with the same 14.7% delta. This consistency suggests that the Xeon’s advantage is structural, not workload-specific.

Single-core tests follow the same pattern. Cinebench R15 single-core gives the Xeon 93 points and the i7-4940MX 81 points, a 14.8% lead. Cinebench R20 single-core shows 391 versus 341, a 14.7% gap. Cinebench R23 single-core records 932 versus 813, a 14.6% difference. The near-identical deltas across all tests indicate that the Xeon’s Skylake cores provide a roughly 15% performance uplift per clock cycle over Haswell, even when the i7-4940MX has a higher boost clock.

The average benchmark scores in the database reinforce this gap. The Xeon E3-1575M v5 has an average benchmark score of 1910, while the Core i7-4940MX has an average of 1886. Both sit at the 43rd percentile among all CPUs, meaning they are statistically similar in overall ranking despite the Xeon’s wins in these specific tests. The Xeon’s nearest rivals include the AMD Ryzen 5 PRO 2404GE with a delta of 0%, the Intel Xeon E-2314 with a delta of -0.1%, and the Intel Xeon E3-1285 v4 with a delta of 0.1%. The i7-4940MX’s nearest rivals include the Intel Xeon D-1531 with a delta of 0.1%, the Intel Xeon E3-1270L v4 with a delta of 0.2%, and the Intel Xeon E3-1558L v5 with a delta of 0.2%. These rival deltas are all within 0.3%, indicating that both processors are closely grouped with their peers in the overall database.

FAQ

Q: Which processor has a higher boost clock?

A: The Intel Core i7-4940MX has a boost clock of 4.00 GHz, while the Intel Xeon E3-1575M v5 has a boost clock of 3.90 GHz.

Q: What is the memory bandwidth difference between the two?

A: The Xeon E3-1575M v5 supports a memory bandwidth of 34.1 GB/s, while the Core i7-4940MX supports 25.6 GB/s, a difference of 8.5 GB/s.

Q: Does either processor support ECC memory?

A: Yes, the Intel Xeon E3-1575M v5 supports ECC memory. The Intel Core i7-4940MX does not.

Q: Which processor has a higher Cinebench R23 multi-core score?

A: The Intel Xeon E3-1575M v5 scores 6607, compared to 5759 for the Core i7-4940MX, a 14.7% lead.

Q: Are both processors multiplier-unlocked?

A: No, only the Intel Core i7-4940MX has an unlocked multiplier. The Xeon E3-1575M v5 is locked.

Q: What is the process node for each processor?

A: The Xeon E3-1575M v5 uses a 14 nm process, while the Core i7-4940MX uses a 22 nm process.

Specification Differences

The Xeon E3-1575M v5 and Core i7-4940MX differ in several key specifications. The Xeon has a base clock of 3.00 GHz and a boost clock of 3.90 GHz, while the i7-4940MX has a base clock of 3.10 GHz and a boost clock of 4.00 GHz. The Xeon’s TDP is 45 watts, compared to 57 watts for the i7-4940MX. The Xeon uses an Intel BGA 1440 socket, while the i7-4940MX uses Intel Socket G3. The Xeon is built on a 14 nm process with 2,300 million transistors and a 171 mm² die size; the i7-4940MX is on a 22 nm process with 1,400 million transistors and a 177 mm² die size.

Memory support differs: the Xeon supports DDR3 and DDR4, while the i7-4940MX supports only DDR3. The Xeon has a memory bandwidth of 34.1 GB/s, versus 25.6 GB/s for the i7-4940MX. ECC memory is supported on the Xeon but not on the i7-4940MX. Integrated graphics also differ, with the Xeon featuring Iris Pro Graphics P580 and the i7-4940MX featuring Intel HD 4600. The Xeon has a launch MSRP of $1207, while the i7-4940MX has a launch MSRP of $1096. The Xeon is multiplier-locked, whereas the i7-4940MX is multiplier-unlocked. The Xeon’s release date is 2016-01-23, and the i7-4940MX’s is 2014-01-19. Part numbers are SR2QV for the Xeon and SR1PP for the i7-4940MX.

The Verdict

The data points decisively toward the Intel Xeon E3-1575M v5 for anyone seeking raw Cinebench performance. It wins all six head-to-head tests, with deltas ranging from 14.6% to 14.8% over the Core i7-4940MX. The Xeon’s newer Skylake architecture, 14 nm process, higher memory bandwidth, and ECC support make it the superior choice for workstation-class workloads that rely on multi-core rendering or single-threaded responsiveness. Its lower TDP of 45 watts versus 57 watts also indicates better power efficiency, though the database does not include thermal measurements.

The Core i7-4940MX, however, retains relevance for a specific user profile. Its unlocked multiplier allows overclocking, a feature the Xeon lacks, which could narrow the performance gap in real-world use if the user is willing to push clocks higher. The i7-4940MX also has a lower launch MSRP of $1096, which may appeal to cost-conscious buyers, though pricing is not a performance factor. Its higher base and boost clocks, 3.10 GHz and 4.00 GHz respectively, do not translate into benchmark wins, but they indicate a capable design for its era.

For users who prioritize out-of-the-box performance, the Xeon E3-1575M v5 is the clear pick. Its consistent 14.7% advantage across every Cinebench test, from R15 to R23, shows that Skylake’s IPC gains over Haswell are substantial. The Xeon’s support for DDR4 and ECC memory also future-proofs it for server or workstation use, whereas the i7-4940MX is limited to DDR3 and lacks ECC. The i7-4940MX suits overclocking enthusiasts who value manual tuning and a lower initial cost, but the benchmark data shows it cannot match the Xeon’s stock performance. Both processors are end-of-life, so availability may vary, but the recorded measurements favor the Xeon without qualification.