Intel Core i7-980X vs Intel Xeon E3-1265L v4 Comparison

The data shows a surprising result: the newer, lower-power, four-core Intel Xeon E3-1265L v4 consistently outperforms the older, six-core Intel Core i7-980X in every recorded benchmark. Despite having two fewer cores, the Xeon’s newer architecture and higher per-core efficiency deliver a clean sweep across all six head-to-head Cinebench tests. The Core i7-980X, a 2010 desktop flagship, retains its advantage only in qualitative specifications like more cores, a higher base clock, and support for triple-channel memory, but the measured performance numbers favor the Xeon in every workload tested.

The Verdict

The benchmark data is unambiguous: the Intel Xeon E3-1265L v4 is the faster processor in this comparison. It wins all six head-to-head tests, with margins ranging from 1.8% to 2.4% in Cinebench R15, R20, and R23, both single-core and multi-core. The Xeon’s multi-core wins are particularly notable because it achieves them with only 4 cores and 8 threads, while the Core i7-980X has 6 cores and 12 threads. This indicates the Xeon’s Broadwell architecture delivers substantially higher instructions per clock, enough to overcome a 50% disadvantage in core count.

For a user prioritizing raw single-threaded responsiveness, the Xeon E3-1265L v4 is again the choice, leading by 2.4% in Cinebench R15 single-core (84 vs 82) and 1.9% in R23 single-core (834 vs 818). The Core i7-980X does offer an unlocked multiplier and 12 threads, which matters for legacy software that scales poorly with newer architectures, but the recorded data shows no benchmark where this translates into a win. The Xeon E3-1265L v4 is the correct pick for anyone who needs the fastest measured performance, especially in multi-threaded rendering, while the Core i7-980X is only preferable for users who specifically require its older platform features, such as triple-channel DDR3 memory, or who intend to overclock, as its unlocked multiplier allows for manual frequency adjustment.

FAQ

Q: Which processor has more cores and threads?

A: The Intel Core i7-980X has 6 cores and 12 threads, while the Intel Xeon E3-1265L v4 has 4 cores and 8 threads. Despite this, the Xeon wins all multi-core benchmarks.

Q: What is the difference in power consumption?

A: The Core i7-980X has a TDP of 130 watts, while the Xeon E3-1265L v4 has a TDP of 35 watts. The Xeon delivers higher performance while consuming less than a third of the power budget.

Q: Do these processors support ECC memory?

A: Yes, the Intel Xeon E3-1265L v4 supports ECC memory. The Intel Core i7-980X does not support ECC memory.

Q: What is the best multi-core benchmark result for each?

A: In Cinebench R23 multi-core, the Xeon E3-1265L v4 scores 5910, while the Core i7-980X scores 5797. The Xeon leads by 1.9% in this test.

Q: Which processor has integrated graphics?

A: The Intel Xeon E3-1265L v4 includes Intel Iris Pro P6300 integrated graphics. The Intel Core i7-980X has no integrated graphics.

Q: How do these processors compare to their nearest rivals in the database?

A: The Core i7-980X has an average benchmark score of 1746, placing it at the 41st percentile, with its closest rival being the Intel Core i5-8269U at a 0.1% difference. The Xeon E3-1265L v4 has an average score of 1709, at the 40th percentile, with its closest rival being the Intel Xeon E5-1620 v3 at a 0% difference.

Architecture Differences

The architectural gap between these two processors is vast, reflecting a five-year generational leap. The Core i7-980X is built on Intel’s Westmere architecture, codenamed Gulftown, using a 32 nm process node. It packs 1,170 million transistors onto a 239 mm² die. In contrast, the Xeon E3-1265L v4 uses the Broadwell architecture, codenamed Broadwell-DT, on a much smaller 14 nm process node, with a die size of 182 mm² and no transistor count listed in the database.

The Core i7-980X features a large 12 MB shared L3 cache, while the Xeon E3-1265L v4 has a smaller 6 MB shared L3 cache. Both have identical L1 and L2 cache sizes per core: 64 KB and 256 KB respectively. The Xeon’s advantage comes from its newer microarchitecture, which delivers higher single-thread performance despite lower clock speeds and a smaller cache. The Xeon also supports a newer PCIe generation, Gen 3 with 16 lanes (CPU only), compared to the Core i7-980X’s PCIe Gen 2. Memory support also differs: the Xeon uses a dual-channel DDR3 bus with a listed bandwidth of 29.9 GB/s, while the Core i7-980X uses a triple-channel DDR3 bus with no bandwidth figure recorded.

The Xeon includes Intel Iris Pro P6300 integrated graphics, a feature entirely absent from the Core i7-980X, which relies on a discrete graphics card. The Xeon also has ECC memory support, critical for error correction in server workloads, while the Core i7-980X lacks it. The Xeon’s multiplier is locked, preventing overclocking, whereas the Core i7-980X has an unlocked multiplier for enthusiast tuning. Finally, the Xeon is a 14 nm part designed for a 35 watt TDP, while the Core i7-980X is a 32 nm part with a 130 watt TDP, underscoring the efficiency gains of the newer process.

Specification Differences

The two processors differ across nearly every major specification category. Core count: the Core i7-980X has 6 cores and 12 threads, the Xeon E3-1265L v4 has 4 cores and 8 threads. Clock speeds: the Core i7-980X has a base clock of 3.33 GHz and a boost clock of 3.60 GHz, while the Xeon has a base clock of 2.30 GHz and a boost clock of 3.30 GHz. Thermal design power: the Core i7-980X is rated at 130 watts, the Xeon at 35 watts. Socket: the Core i7-980X uses Intel Socket 1366, the Xeon uses Intel Socket 1150. Process node: 32 nm for the Core i7-980X, 14 nm for the Xeon.

Cache: the Core i7-980X has 12 MB of shared L3 cache, the Xeon has 6 MB. Memory bus: the Core i7-980X is triple-channel, the Xeon is dual-channel with a measured bandwidth of 29.9 GB/s. ECC support: the Core i7-980X does not support it, the Xeon does. PCIe: the Core i7-980X is Gen 2, the Xeon is Gen 3 with 16 lanes (CPU only). Integrated graphics: the Core i7-980X has none, the Xeon has Intel Iris Pro P6300. The multiplier is unlocked on the Core i7-980X and locked on the Xeon. Release dates are March 2010 for the Core i7-980X and June 2015 for the Xeon. The Xeon has a launch MSRP of $417, while the Core i7-980X has no recorded launch price.

Head-to-Head Benchmarks

The Xeon E3-1265L v4 wins every recorded benchmark, with a total of 6 wins to 0 for the Core i7-980X. The margins are consistent, hovering around 2%. In Cinebench R15 multi-core, the Xeon scores 595 against 584 for the Core i7-980X, a 1.8% lead. The single-core R15 test shows the Xeon at 84 versus 82, a 2.4% advantage, which is the largest margin in the entire comparison.

In Cinebench R20, the Xeon leads multi-core with 2482 versus 2434, a 1.9% difference, and single-core with 350 versus 343, a 2% difference. The R23 results follow the same pattern: multi-core 5910 versus 5797, a 1.9% lead, and single-core 834 versus 818, also a 1.9% lead. The near-identical deltas across all three Cinebench versions suggest a consistent architectural advantage rather than a workload-specific quirk.

The most striking finding is that the Xeon wins multi-core tests with fewer cores. The Core i7-980X’s 6 cores and 12 threads should theoretically provide a 50% core-count advantage, but the Xeon’s higher per-core efficiency, enabled by the 14 nm Broadwell architecture, overcomes this. The data shows the Xeon is 1.8% to 1.9% faster in multi-core tests, meaning the Core i7-980X’s extra cores are effectively neutralized by the Xeon’s superior IPC (instructions per clock). Average benchmark scores confirm this: the Core i7-980X averages 1746 points, while the Xeon averages 1709 points, a 2.1% gap that favors the Core i7-980X only in aggregate, but this is driven by the Geekbench results where the Core i7-980X has scores (3247 multi-core, 659 single-core) not available for the Xeon, which lacks Geekbench entries in the database.

Where Each One Wins

The Xeon E3-1265L v4 wins in every measured performance category. It is faster in single-threaded workloads, leading by 2.4% in R15 and 1.9% in R20 and R23. This makes it the better choice for applications that rely on per-core speed, such as older games or lightly threaded productivity tools. It is also faster in multi-threaded rendering, leading by 1.8% to 1.9% across R15, R20, and R23, which covers modern video encoding, 3D rendering, and compilation tasks. Its 35 watt TDP makes it suitable for compact or low-power systems, and its integrated Intel Iris Pro P6300 graphics eliminate the need for a discrete GPU in basic display output. ECC memory support is a decisive factor for server or workstation builds where data integrity is paramount.

The Core i7-980X has no benchmark wins to its name, but it retains qualitative advantages. Its 6 cores and 12 threads provide double the thread count of the Xeon, which can benefit legacy software that is not optimized for newer architectures. Its unlocked multiplier allows for overclocking, potentially closing the performance gap in scenarios where the user is willing to accept higher power consumption and heat. The triple-channel memory bus offers higher theoretical memory bandwidth, though the database does not record a comparative bandwidth figure for the Core i7-980X. Finally, its 130 watt TDP and 2010 release date place it in a different era of computing, and for users with existing Socket 1366 motherboards, it may represent a drop-in upgrade path. However, based on the recorded benchmarks, the Xeon E3-1265L v4 is the superior processor in every measurable way.