Intel Core i7-8665U vs Intel Xeon E3-1268L v5 Comparison

Head-to-Head Benchmarks

The recorded data shows a complete sweep for the Intel Xeon E3-1268L v5 across all six Cinebench comparisons. In every test, the Xeon posts a higher score than the Core i7-8665U, though the margins are consistently narrow, ranging from 2.7 percent to 3.2 percent.

Starting with the multi-core results, the Xeon E3-1268L v5 scores 542 in Cinebench R15 multi-core against 527 for the Core i7-8665U, a 2.8 percent advantage. In Cinebench R20 multi-core, the Xeon reaches 2260 while the Core i7 scores 2197, widening the gap slightly to 2.9 percent. The Cinebench R23 multi-core test shows the Xeon at 5383 and the Core i7 at 5232, again a 2.9 percent edge for the Xeon.

Single-core results follow the same pattern but with slightly different margins. In Cinebench R15 single-core, the Xeon scores 76 versus 74 for the Core i7, a 2.7 percent lead. The Cinebench R20 single-core test gives the Xeon 319 points and the Core i7 309 points, which is the largest relative difference in the entire comparison at 3.2 percent. Finally, Cinebench R23 single-core shows the Xeon at 760 and the Core i7 at 738, a 3 percent advantage.

The average benchmark score for the Xeon E3-1268L v5 is 1557, while the Core i7-8665U averages 1513. That difference places the Xeon at the 39th percentile among all CPUs in the database, with the Core i7 one point lower at the 38th percentile. These are close standings, and the percentile figures reinforce that both processors occupy a similar performance tier despite the Xeon winning every direct comparison.

Looking at the nearest rivals in the database provides additional context. The Xeon E3-1268L v5 matches the AMD FX-8350 exactly at an average score of 1557 with a delta of 0 percent. It also sits near the Intel Core i3-1115G4E, which scores 1559 for a delta of negative 0.1 percent, and the AMD Opteron 6276 at 1560 for negative 0.2 percent. On the other side, the Intel Core i3-9300 scores 1554 with a positive 0.2 percent delta, meaning the Xeon edges it out by a hair.

The Core i7-8665U, meanwhile, has its nearest rival in the Intel Pentium Gold G7400E at 1524, a negative 0.7 percent delta. The Intel Core i5-4670S scores 1526 for a negative 0.9 percent delta, and the Intel Core i5-7440HQ also scores 1527 for negative 0.9 percent. The Intel Core i3-8100T trails slightly at 1500 with a positive 0.9 percent delta, meaning the Core i7 outperforms that chip by nearly a full point on the database's scale.

The data indicates that the Xeon E3-1268L v5 holds a consistent, though modest, lead in every benchmark category. No test shows the Core i7-8665U pulling ahead, and the win count stands at 6 for the Xeon and 0 for the Core i7.

FAQ

Q: Which processor wins the most benchmarks in this comparison?

A: The Intel Xeon E3-1268L v5 wins all six head-to-head Cinebench tests. The Core i7-8665U does not win any of the recorded comparisons.

Q: How large is the performance gap between the two in multi-core workloads?

A: The Xeon leads by 2.8 percent in Cinebench R15 multi-core, 2.9 percent in R20 multi-core, and 2.9 percent in R23 multi-core. These are consistent but small margins.

Q: Is the single-core performance difference larger or smaller than multi-core?

A: The single-core gaps are slightly more varied. The Xeon leads by 2.7 percent in R15 single-core, 3.2 percent in R20 single-core, and 3 percent in R23 single-core. The R20 single-core test shows the largest gap of any comparison.

Q: How do the two processors rank against all CPUs in the database?

A: The Xeon E3-1268L v5 sits at the 39th percentile, and the Core i7-8665U sits at the 38th percentile. Their average benchmark scores are 1557 and 1513, respectively.

Q: What are the closest rival processors to each of these chips?

A: For the Xeon, the AMD FX-8350 matches its average score exactly at 1557. For the Core i7, the Intel Pentium Gold G7400E is the nearest rival at 1524, which is 0.7 percent lower.

Q: Do both processors support the same memory types?

A: Yes, both support DDR3 and DDR4 memory in a dual-channel configuration. However, the Xeon has a memory bandwidth of 34.1 GB/s, while the Core i7 has a higher bandwidth of 38.4 GB/s.

Where Each One Wins

The Xeon E3-1268L v5 is the winner in every recorded benchmark, so the use-case split is driven by the size of its advantages and the surrounding specifications rather than any outright Core i7 wins.

For workloads that depend heavily on multithreaded rendering, the Xeon's lead in Cinebench R23 multi-core at 5383 versus 5232 makes it the safer choice. The margin is only 2.9 percent, but it holds up consistently across all three Cinebench versions. Anyone running sustained multi-core tasks on a fixed platform will see a small but repeatable benefit from the Xeon.

Single-threaded responsiveness also favors the Xeon, with a 3.2 percent edge in Cinebench R20 single-core being the largest delta in the dataset. For applications that are latency-sensitive or rely on quick bursts of single-core activity, the Xeon again comes out ahead, though the advantage is small.

However, the Core i7-8665U has its own territory. Its memory bandwidth is higher at 38.4 GB/s versus 34.1 GB/s, which can matter for memory-bound tasks even if the compute scores are lower. The Core i7 is also a mobile part with a lower TDP of 15 watts, making it suitable for compact, power-constrained systems where the Xeon's 35-watt TDP would be harder to accommodate. The Xeon requires an Intel Socket 1151 platform, while the Core i7 uses Intel BGA 1528, a soldered mobile socket.

The Core i7 also carries the UHD Graphics 620 integrated GPU, while the Xeon has HD Graphics P530. In scenarios where the integrated graphics matter and the processor is the only GPU available, the choice of iGPU could influence platform selection, though the database does not include graphics benchmarks for either chip.

Specification Differences

The two processors differ in several key specification fields. The Xeon E3-1268L v5 has a base clock of 2.40 GHz and a boost clock of 3.40 GHz. The Core i7-8665U lists a base clock of 1900.00 MHz and a boost clock of 4.80 GHz. The boost clock is substantially higher on the Core i7, but the base clock is much lower.

Thermal design power differs significantly. The Xeon is rated at 35 watts, while the Core i7 is rated at 15 watts. The socket types also differ: the Xeon uses Intel Socket 1151, and the Core i7 uses Intel BGA 1528.

Memory bandwidth is another differentiator. The Xeon supports 34.1 GB/s, while the Core i7 supports 38.4 GB/s. ECC memory support is present on the Xeon but not on the Core i7. The integrated graphics differ as well, with the Xeon featuring HD Graphics P530 and the Core i7 featuring UHD Graphics 620.

The market segments are distinct. The Xeon is classified as a Server/Workstation part, while the Core i7 is a Mobile part. Release dates differ by roughly three years: the Xeon was released in 2015, and the Core i7 was released in 2018. The launch MSRP for the Xeon is $377, and the launch MSRP for the Core i7 is $409.

The part numbers are SR2LQ for the Xeon and SRF9W for the Core i7. Both processors have 4 cores and 8 threads, and neither has an unlocked multiplier.

Architecture Differences

Both processors are built on Intel's 14 nm process node and share the same per-core cache layout: 64 KB of L1 per core and 256 KB of L2 per core. Both have 8 MB of shared L3 cache. The transistor count for the Xeon is listed as 1,750 million, while the Core i7 has no recorded transistor count in the database. The Xeon has a die size of 122 mm², while the Core i7 has no recorded die size.

The core architecture families differ. The Xeon uses the Skylake architecture with the codename Skylake-DT, and its generation is listed as Xeon E3 (Skylake-DT). The Core i7 uses the Whiskey Lake architecture with the codename Whiskey Lake-U, and its generation is listed as Core i7 (Whiskey Lake).

The Xeon is produced by Intel and comes from the Intel foundry, as does the Core i7. Both support DDR3 and DDR4 memory in dual-channel mode. PCIe support is identical: Gen 3 with 16 lanes from the CPU only.

ECC memory is a notable architectural difference. The Xeon supports ECC memory, which is typical for its Server/Workstation segment. The Core i7 does not support ECC, which is consistent with its mobile consumer positioning.

The production status for both is end-of-life, meaning neither is currently an active production part.

The Verdict

The benchmark data is unambiguous: the Intel Xeon E3-1268L v5 outperforms the Intel Core i7-8665U in every recorded Cinebench test. The margins are narrow, between 2.7 and 3.2 percent, but they are uniform across all six comparisons. The Xeon also holds a higher average benchmark score at 1557 against 1513, and it sits one percentile point higher in the overall CPU ranking.

For a user building a system around an Intel Socket 1151 platform with a 35-watt thermal budget, the Xeon E3-1268L v5 is the correct pick based on raw compute performance. It also brings ECC memory support, which is absent on the Core i7, making it the appropriate choice for error-sensitive workloads in a server or workstation context. The launch MSRP of $377 for the Xeon reflects its positioning in that segment.

The Core i7-8665U, on the other hand, is a mobile part with a 15-watt TDP and a BGA 1528 socket. Its higher boost clock of 4.80 GHz does not translate into higher benchmark scores in the recorded data, but its lower power envelope and higher memory bandwidth of 38.4 GB/s give it a role in compact, low-power designs where the Xeon's platform requirements are not feasible. The launch MSRP of $409 places it above the Xeon in price, but the database records no performance win to justify that premium.

For anyone selecting between these two based purely on the recorded benchmarks, the Xeon E3-1268L v5 is the faster processor. For anyone constrained by power, socket, or form factor, the Core i7-8665U is the only viable option, and its performance deficit is small enough that the trade-off may be acceptable. The data does not support choosing the Core i7 for performance reasons, only for platform or power reasons.