Intel Core i7-8705G vs Intel Xeon E3-1275 v5 Comparison

The Intel Core i7-8705G and Intel Xeon E3-1275 v5 are both 4-core, 8-thread Intel parts from the 14 nm era, but they target completely different corners of the market. The i7-8705G is a mobile Kaby Lake-G processor with integrated Radeon graphics, while the Xeon E3-1275 v5 is a Skylake-based server/workstation chip. Benchmark data shows a clear, consistent winner in CPU performance: the Xeon E3-1275 v5 takes all six head-to-head tests, with margins ranging from 8.4% to 9%. However, the i7-8705G is not without its own strengths, particularly in platform capabilities and power efficiency, which this analysis breaks down by workload and architecture.

Where Each One Wins

The Xeon E3-1275 v5 wins every single CPU benchmark in this comparison. In Cinebench R15 multicore, it scores 712 against the i7-8705G's 651, an 8.6% advantage. The single-core R15 result is 100 versus 91, a 9% lead. This pattern holds across every version of Cinebench: R20 multicore (2967 vs 2714, 8.5%), R20 single-core (418 vs 383, 8.4%), R23 multicore (7065 vs 6464, 8.5%), and R23 single-core (997 vs 912, 8.5%). The Xeon's wins are not flukes or workload-specific quirks; they are remarkably consistent, staying within a tight 8.4% to 9% band across all six tests.

The i7-8705G has zero benchmark wins in this head-to-head, but that does not mean it has no use cases. Its advantage lies outside pure CPU compute. The i7-8705G has a 65 W TDP compared to the Xeon's 80 W, making it a more power-efficient option for mobile or compact systems. It also supports DDR4 memory with a higher theoretical bandwidth of 38.4 GB/s versus the Xeon's 34.1 GB/s. For workloads that are memory-bandwidth sensitive but not CPU-core sensitive, the i7-8705G could close the gap, even though the benchmark data here does not show it winning any tests. The i7-8705G also has an unlocked market position as a mobile part with a BGA socket, meaning it is soldered to the board, which is a different design philosophy than the Xeon's socketed LGA 1151.

The Xeon's wins are decisive for CPU-bound tasks like video rendering, 3D modeling, and software compilation. The i7-8705G's wins, if any, would be in scenarios where its lower TDP and higher memory bandwidth matter more than raw core performance. The Geekbench scores tell a slightly different story: the i7-8705G has a Geekbench multicore score of 3968 and a single-core score of 1277. The Xeon E3-1275 v5 does not have Geekbench scores in this data pack, so we cannot directly compare those, but the Cinebench results are unambiguous: the Xeon is faster in every measured CPU test.

Architecture Differences

The two processors come from different Intel microarchitectures. The i7-8705G is built on Kaby Lake (specifically Kaby Lake-G), while the Xeon E3-1275 v5 is Skylake-DT. Both use a 14 nm process node from Intel, and both have the same core configuration: 4 cores, 8 threads, 64 KB of L1 cache per core, 256 KB of L2 cache per core, and 8 MB of shared L3 cache. The die sizes are nearly identical, with the i7-8705G at 125 mm² and the Xeon at 122 mm², and the Xeon's transistor count is listed at 1,750 million.

Clock speeds differ significantly. The i7-8705G has a base clock of 3.10 GHz and a boost clock of 4.10 GHz. The Xeon E3-1275 v5 has a higher base clock of 3.60 GHz but a slightly lower boost clock of 4.00 GHz. This explains the Xeon's consistent lead in single-core tests: it starts from a higher base frequency, and its boost is close enough to the i7's that the Xeon maintains an edge. The i7-8705G's higher boost clock (4.10 vs 4.00) is not enough to overcome the Xeon's base clock advantage in sustained workloads, as shown by the multicore results.

Memory support is a key differentiator. The i7-8705G supports only DDR4, while the Xeon E3-1275 v5 supports both DDR3 and DDR4. Both are dual-channel, but the i7-8705G has a higher peak memory bandwidth (38.4 GB/s vs 34.1 GB/s). ECC memory is a major split: the Xeon supports ECC, the i7-8705G does not. This makes the Xeon a natural fit for servers and workstations where data integrity is critical. The i7-8705G also has a more limited PCIe configuration: Gen 3 with 8 lanes (CPU only), versus the Xeon's Gen 3 with 16 lanes (CPU only). For systems needing more PCIe lanes for GPUs or NVMe storage, the Xeon has a clear advantage.

Integrated graphics differ as well. The i7-8705G uses Intel HD Graphics 630, while the Xeon uses HD Graphics P530. The i7-8705G is part of the Kaby Lake-G family, which historically pairs the CPU with a discrete-class GPU on the same package, but the FACT PACK only lists the Intel HD Graphics 630 iGPU for the i7. The Xeon's market segment is "Server/Workstation," while the i7-8705G is "Mobile." The i7-8705G was released in January 2018, while the Xeon was released in October 2015. Both are end-of-life products. The Xeon has a launch MSRP of $350, which can be stated once as such.

Head-to-Head Benchmarks

The largest single win for the Xeon E3-1275 v5 is in Cinebench R15 single-core, where it scores 100 versus the i7-8705G's 91, a 9% difference. This is a substantial margin for a single-threaded test and reflects the Xeon's higher 3.60 GHz base clock. In multicore R15, the Xeon wins 712 to 651, an 8.6% edge. The multicore advantage is slightly smaller than the single-core advantage, suggesting that the i7-8705G's higher boost clock helps when all cores are active, but not enough to close the gap.

Cinebench R20 results follow the same pattern. The Xeon wins multicore 2967 to 2714 (8.5%) and single-core 418 to 383 (8.4%). The margins are nearly identical to R15, indicating that the performance relationship is stable across different Cinebench versions. Cinebench R23 shows the Xeon winning multicore 7065 to 6464 (8.5%) and single-core 997 to 912 (8.5%). The R23 single-core margin is 8.5%, which is slightly smaller than the R15 single-core margin of 9%, but still a clear win.

The i7-8705G's best showing relative to the Xeon is in the R20 single-core test, where it trails by only 8.4%. Its worst relative performance is in R15 single-core, where it trails by 9%. Across all six tests, the Xeon's average advantage is approximately 8.6%. The i7-8705G's Geekbench scores (3968 multicore, 1277 single-core) are not directly comparable to the Xeon because the Xeon has no Geekbench data in this pack. However, the i7-8705G's overall percentile ranking is 46th among all CPUs, while the Xeon sits at 45th, meaning they are nearly identical in overall performance distribution despite the Xeon winning every head-to-head test. The average benchmark scores are also close: 2058 for the i7-8705G and 2043 for the Xeon, a difference of less than 1%.

The Verdict

The data is clear: for pure CPU performance, the Intel Xeon E3-1275 v5 is the better processor. It wins all six head-to-head benchmarks, with margins between 8.4% and 9%. This makes it the stronger choice for CPU-bound workloads such as video encoding, 3D rendering, and scientific computing. The Xeon also supports ECC memory, which is a requirement for many server and workstation applications. Its higher base clock of 3.60 GHz gives it a consistent edge in both single-threaded and multi-threaded tasks, even though the i7-8705G has a higher boost clock of 4.10 GHz.

The Intel Core i7-8705G is not a bad CPU, but it loses every benchmark in this comparison. Its strengths lie elsewhere: a lower 65 W TDP versus the Xeon's 80 W, higher memory bandwidth (38.4 GB/s vs 34.1 GB/s), and a mobile form factor (BGA 2270) that allows for compact, power-efficient systems. If you are building a laptop or a small-form-factor PC where power draw and heat are more important than raw CPU speed, the i7-8705G is the more sensible choice. It also has a higher Geekbench multicore score (3968) than its average benchmark score would suggest, indicating strong performance in certain workloads.

For a system builder choosing between these two, the decision hinges on the use case. If the task is heavy multi-threaded rendering or ECC-memory-dependent server work, the Xeon E3-1275 v5 is the only viable option based on this data. If the goal is a low-power mobile or compact system with adequate CPU performance, the i7-8705G's lower TDP and higher memory bandwidth make it a better fit, even though it loses every CPU benchmark. The Xeon's 16 PCIe lanes (versus the i7's 8) also make it better for systems with multiple expansion cards. In short, the Xeon wins on performance and features; the i7-8705G wins on power efficiency and form factor.

FAQ

Q: Which CPU is faster in Cinebench R23 multicore?

A: The Intel Xeon E3-1275 v5, scoring 7065 versus the Intel Core i7-8705G's 6464, an 8.5% advantage.

Q: Does the Intel Core i7-8705G support ECC memory?

A: No, the i7-8705G does not support ECC memory. The Xeon E3-1275 v5 does support ECC.

Q: What is the TDP difference between the two processors?

A: The Intel Core i7-8705G has a TDP of 65 W, while the Intel Xeon E3-1275 v5 has a TDP of 80 W.

Q: How many Cinebench tests did each CPU win?

A: The Intel Xeon E3-1275 v5 won all six head-to-head Cinebench tests. The Intel Core i7-8705G won zero.

Q: Which CPU has higher memory bandwidth?

A: The Intel Core i7-8705G has a memory bandwidth of 38.4 GB/s, compared to the Xeon E3-1275 v5's 34.1 GB/s.

Q: What is the launch MSRP of the Intel Xeon E3-1275 v5?

A: The launch MSRP is $350. The i7-8705G has no listed launch MSRP in the data.