Intel Core i3-5157U vs Intel Core i7-860 Comparison

The Verdict

The recorded data separates these two processors cleanly. The Intel Core i7-860 wins every single head-to-head benchmark in the database, taking all five Cinebench comparisons with deltas between 16.7% and 16.9%. It holds a 24th percentile ranking among all CPUs, while the Core i3-5157U sits just one point lower at the 23rd percentile. The i7-860 is the clear choice for anyone needing raw compute throughput, particularly in multi-threaded workloads where its 4 cores and 8 threads double the i3's 2 cores and 4 threads. The Core i3-5157U, however, belongs in a different context: it is a mobile part with a 28W TDP and integrated Iris 6100 graphics, making it the sensible pick for compact, power-conscious systems where the i7-860's 95W desktop requirement is simply not viable. The i7-860 is end-of-life desktop silicon from 2009; the i3-5157U is end-of-life mobile silicon from 2015. Choose the i7-860 for compute, the i3-5157U for portability and integrated graphics.

Where Each One Wins

The Intel Core i7-860 wins in every benchmark category that involves sustained processing. Its Cinebench R15 multicore score of 259 beats the i3-5157U's 222 by 16.7%. The R20 multicore result shows 1081 against 925, a 16.9% edge. The R23 multicore test records 2574 versus 2203, again 16.8% ahead. Even in single-core tests, the older Nehalem part leads: R20 single-core is 152 versus 130 (16.9% delta), and R23 single-core is 363 versus 311 (16.7% delta). The i7-860 also has a larger 8 MB shared L3 cache versus the i3's 3 MB, and its base clock of 2.80 GHz with a 3.47 GHz boost gives it a frequency advantage over the i3's fixed 2.50 GHz (no boost clock is listed for the i3).

The Intel Core i3-5157U wins on platform attributes rather than raw benchmarks. It integrates Intel Iris 6100 graphics, which the i7-860 lacks entirely. Its TDP is 28W versus 95W, a massive reduction for thermal and battery considerations. It supports DDR3 memory with a rated bandwidth of 29.9 GB/s, whereas the i7-860's memory bandwidth is not recorded. The i3 uses a 14 nm process with 1,900 million transistors on a 133 mm² die, versus the i7's 45 nm process with 774 million transistors on a 296 mm² die. The i3 also has a faster PCIe implementation in terms of lane count? No, the i7 has 16 lanes, the i3 has 12 lanes, both Gen 2. The i3's single-core Geekbench scores are not matched by the i7 in the head-to-head table, but the i3 does have recorded Geekbench results: 1568 multicore and 778 singlecore. The i7 has no Geekbench entry, so cross-comparison there is not possible from the data.

Architecture Differences

The two chips come from different Intel generations and design philosophies. The i7-860 is a Lynnfield part based on the Nehalem architecture, built on a 45 nm process at Intel's foundry. It packs 774 million transistors into a 296 mm² die. The i3-5157U is a Broadwell-U part based on the Broadwell architecture, built on a 14 nm process, also by Intel, with 1,900 million transistors on a much smaller 133 mm² die. The transistor density jump is enormous: the newer process crams more than double the transistors into less than half the die area.

Core counts differ fundamentally. The i7-860 has 4 physical cores and 8 threads via Hyper-Threading. The i3-5157U has 2 physical cores and 4 threads. Cache hierarchies follow the same pattern: both have 64 KB L1 per core and 256 KB L2 per core, but the i7's shared L3 is 8 MB while the i3's shared L3 is 3 MB. The i7's larger cache is a direct contributor to its benchmark leads.

Socket and platform targets diverge completely. The i7-860 uses Intel Socket 1156, a desktop socket, with PCIe Gen 2 and 16 lanes from the CPU. The i3-5157U uses Intel BGA 1168, a soldered mobile package, with PCIe Gen 2 and 12 lanes from the CPU. The i7 has no integrated graphics; the i3 includes Intel Iris 6100. Memory support is DDR3 dual-channel for both, but only the i3 has a published memory bandwidth figure of 29.9 GB/s. Neither supports ECC memory, and neither has an unlocked multiplier. The i7's part number is SLBJJ; the i3's is SR26M. The i7 launched in September 2009; the i3 launched in February 2015. The i3's launch MSRP is $315, stated once here as recorded.

FAQ

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

A: The Intel Core i7-860. It wins all three Cinebench multicore tests: R15 at 259 versus 222, R20 at 1081 versus 925, and R23 at 2574 versus 2203. The deltas range from 16.7% to 16.9%.

Q: Does the Core i3-5157U win any benchmark in the database?

A: No. The head-to-head table records 5 wins for the i7-860 and 0 wins for the i3-5157U. The i3 does have Geekbench scores (1568 multicore, 778 singlecore), but the i7 has no Geekbench entry for comparison.

Q: What are the power requirements?

A: The i7-860 has a TDP of 95W, designed for desktop Socket 1156. The i3-5157U has a TDP of 28W, designed for mobile BGA 1168. This is a 67W difference in favor of the i3.

Q: Does either chip have integrated graphics?

A: Only the i3-5157U includes integrated graphics, specifically Intel Iris 6100. The i7-860 has no integrated graphics listed.

Q: Which has the larger cache?

A: The i7-860 has 8 MB of shared L3 cache. The i3-5157U has 3 MB of shared L3 cache. Both have 64 KB L1 per core and 256 KB L2 per core.

Q: Are these chips still in production?

A: No. Both are marked as end-of-life in the database. The i7-860 was released in September 2009, and the i3-5157U was released in February 2015.

Head-to-Head Benchmarks

The most striking pattern in the head-to-head data is uniformity. Every Cinebench test, regardless of version or thread count, shows the i7-860 ahead by roughly 17%. This consistency suggests the performance gap stems from a fundamental architectural advantage, not a workload-specific quirk.

Starting with Cinebench R15 multicore, the i7-860 scores 259 against the i3-5157U's 222. That is a delta of 16.7%. The i7's extra two physical cores and four threads directly translate into a 37-point lead. In R20 multicore, the scores are 1081 versus 925, a 156-point difference and a 16.9% delta. The absolute gap grows with the workload's duration, indicating the i7 can sustain its advantage.

Single-core results tell a subtler story. The i7-860's R20 single-core score is 152, while the i3-5157U manages 130. That is a 16.9% delta. In R23 single-core, the i7 scores 363 and the i3 scores 311, a 16.7% delta. Even without multi-threading, the older desktop chip beats the newer mobile chip. The i7's higher base clock (2.80 GHz versus 2.50 GHz) and boost capability (3.47 GHz versus no boost listed) likely explain this advantage, along with the larger 8 MB L3 cache.

The closest competition between the two is in R23 multicore, where the i7's 2574 beats the i3's 2203 by 371 points, a 16.8% delta. The widest relative gap appears in R20 single-core and R20 multicore, both at 16.9%. Across all five benchmarks, the average delta is approximately 16.8%, with no test falling outside the narrow 16.7% to 16.9% band.

For context from the nearest rivals, the i7-860's average benchmark score is 886, which puts it essentially level with the AMD PRO A8-8650B (887, delta -0.1%), the Intel Pentium G4560T (887, delta -0.1%), the Intel Xeon X5550 (888, delta -0.2%), and the Intel Core i3-6100 (888, delta -0.3%). The i3-5157U's average score is 877, sitting near the AMD Ryzen 3 2300U (880, delta -0.3%), the AMD PRO A12-8870E (880, delta -0.4%), the Intel Core i3-1000NG4 (881, delta -0.4%), and the AMD Phenom II X6 1035T (881, delta -0.5%). The 9-point difference between the two CPUs' average scores (886 versus 877) is small, but the head-to-head tests amplify the i7's edge in sustained Cinebench loads.

The data also shows the i3-5157U has a recorded memory bandwidth of 29.9 GB/s, a feature absent from the i7's specification sheet. This does not translate into benchmark wins in the recorded tests, but it does indicate the mobile platform has a defined memory ceiling. The i7's memory bandwidth is simply not documented, so no comparison is possible there.

In summary, the head-to-head benchmarks consistently favor the i7-860 across every measured test, with deltas that are remarkably stable. The i3-5157U's advantages are not in raw compute but in power envelope, integrated graphics, and process efficiency. A buyer choosing between these two should base the decision on platform needs: desktop compute versus mobile integration. The numbers leave no ambiguity about which one is faster.