CPU Comparison

The Intel Core i3-5157U and the Intel Core i7-860 represent two very different eras of Intel design, but the benchmark data places them in a surprisingly close performance tier. The i7-860 wins every single head-to-head benchmark in this comparison, yet the overall average scores are nearly identical: 877 for the i3-5157U versus 886 for the i7-860. This creates a fascinating dynamic where the older desktop part consistently edges out the newer mobile chip in raw compute, while both land in the bottom quarter of all CPUs, with percentiles of 23 and 24, respectively. The data suggests that platform and power envelope matter more here than raw architectural age.

Head-to-Head Benchmarks

The i7-860 dominates every benchmark listed, but the margins are remarkably consistent. In Cinebench R15 multi-core, the i7-860 scores 259 against the i3-5157U's 222, a 14.3% deficit for the mobile chip. That pattern holds almost exactly across the other multi-threaded tests: Cinebench R20 shows 1081 versus 925 (a 14.4% gap), and Cinebench R23 shows 2574 versus 2203 (also 14.4% behind). The consistency of these numbers indicates a stable performance ceiling difference rather than a workload-specific advantage.

Single-threaded performance tells the same story. In Cinebench R20 single-core, the i7-860 posts 152 versus 130 for the i3-5157U, a 14.5% lead. The R23 single-core test shows 363 versus 311, a 14.3% advantage. It is notable that the i3-5157U does not have a Geekbench head-to-head entry, though its standalone Geekbench scores are 1568 multi-core and 778 single-core, which give it an average benchmark score of 877. The i7-860 lacks Geekbench data entirely, but its five Cinebench results yield an average of 886.

The biggest takeaway from the head-to-head data is that the i7-860 wins all five tests, but never by more than 14.5%. The i3-5157U wins zero tests outright. However, the proximity of the overall average scores, within 1%, suggests that the i3-5157U's performance profile is competitive in aggregate, even if it loses every direct comparison. The i7-860's 4 cores and 8 threads give it a structural advantage in multi-threaded workloads, and its higher base clock of 2.80 GHz with a boost of 3.47 GHz helps in single-threaded tasks.

Where Each One Wins

The i7-860 wins every benchmark in this comparison, so the use-case split is straightforward: it is the stronger processor for any workload measured here. Its wins span both multi-core and single-core tests, meaning it is better for rendering, compilation, and general desktop responsiveness. The 14.3% to 14.5% margins across the board indicate a uniform advantage, not a niche one. For users running Cinebench-style workloads, the i7-860 is the clear choice.

The i3-5157U, despite losing all head-to-head tests, still has a role. Its average benchmark score of 877 is only 9 points below the i7-860's 886, and its nearest rivals include the AMD Ryzen 3 2300U (880, 0.3% ahead) and the AMD PRO A12-8870E (880, 0.4% ahead). This places it in the same performance class as those parts. Where the i3-5157U wins is not in the benchmarks provided, but in its platform characteristics: it is a 28W mobile part with integrated Intel Iris 6100 graphics, while the i7-860 is a 95W desktop part with no integrated graphics. For a low-power mobile system, the i3-5157U is the only viable option in this pairing.

The i7-860's 4 cores and 8 threads give it a clear advantage in heavily threaded applications, as evidenced by its multi-core wins. The i3-5157U's 2 cores and 4 threads cap its multi-threaded potential, but its single-core scores are close enough that the gap is not catastrophic. The data shows the i7-860 is the winner for anyone who needs raw compute, while the i3-5157U is the winner for anyone who needs a compact, low-power solution with built-in graphics.

Architecture Differences

The architectural gap between these two CPUs is substantial. The i3-5157U is built on Broadwell, a 14 nm process, while the i7-860 uses Nehalem on a 45 nm node. This explains the transistor counts: the i3-5157U packs 1,900 million transistors onto a 133 mm² die, whereas the i7-860 has just 774 million transistors on a much larger 296 mm² die. The newer process allows the i3-5157U to achieve better efficiency per transistor, but the i7-860 compensates with more cores and higher clocks.

Cache configurations differ significantly. Both have 64 KB of L1 per core and 256 KB of L2 per core, but the shared L3 cache is where they diverge: the i3-5157U has 3 MB shared, while the i7-860 has 8 MB shared. That 5 MB difference is a major factor in the i7-860's consistent benchmark wins, as larger caches reduce memory latency and improve data reuse. The i3-5157U does have a memory bandwidth advantage, listed at 29.9 GB/s, while the i7-860 has no memory bandwidth figure in the data.

The i3-5157U features integrated Intel Iris 6100 graphics, while the i7-860 has none. This is a critical difference for system builders: the i3-5157U can run a display without a discrete GPU, while the i7-860 requires a separate graphics card. PCIe lane counts also differ, with the i3-5157U offering 12 lanes and the i7-860 offering 16, both Gen 2. The i3-5157U uses the Intel BGA 1168 socket, while the i7-860 uses Intel Socket 1156. Neither processor has an unlocked multiplier, so overclocking is not an option for either.

FAQ

Q: Which processor has a higher average benchmark score?

A: The Intel Core i7-860 has an average benchmark score of 886, versus 877 for the Intel Core i3-5157U. That is a difference of 9 points, or roughly 1%.

Q: How big is the performance gap in multi-core tests?

A: The i7-860 leads by 14.3% in Cinebench R15 multi-core (259 vs 222), 14.4% in R20 multi-core (1081 vs 925), and 14.4% in R23 multi-core (2574 vs 2203).

Q: Does the i3-5157U win any benchmark in the head-to-head comparison?

A: No. The i7-860 wins all five head-to-head benchmarks, covering both single-core and multi-core tests. The i3-5157U has zero wins in this dataset.

Q: What is the difference in integrated graphics support?

A: The i3-5157U includes Intel Iris 6100 integrated graphics, while the i7-860 has no integrated graphics at all. This means the i7-860 requires a discrete GPU for display output.

Q: How do the core and thread counts compare?

A: The i7-860 has 4 cores and 8 threads, while the i3-5157U has 2 cores and 4 threads. The i7-860 also has a higher base clock (2.80 GHz vs 2.50 GHz) and a boost clock of 3.47 GHz, which the i3-5157U lacks entirely.

Q: Are both processors still in production?

A: No. Both are end-of-life parts. The i3-5157U was released on 2015-02-28, and the i7-860 was released on 2009-09-07.

Specification Differences

The two processors differ in nearly every core specification. The i3-5157U has 2 cores and 4 threads, while the i7-860 has 4 cores and 8 threads. Base clocks are 2.50 GHz for the i3-5157U and 2.80 GHz for the i7-860, with the i7-860 also offering a 3.47 GHz boost clock that the i3-5157U does not have. TDP is a major divider: 28W for the mobile i3-5157U versus 95W for the desktop i7-860.

Process technology separates them further: 14 nm for Broadwell versus 45 nm for Nehalem. Transistor counts are 1,900 million versus 774 million, and die sizes are 133 mm² versus 296 mm². L3 cache is 3 MB shared for the i3-5157U and 8 MB shared for the i7-860. Memory bandwidth is listed only for the i3-5157U at 29.9 GB/s. PCIe lanes are 12 for the i3-5157U and 16 for the i7-860, both Gen 2. The i3-5157U has integrated Intel Iris 6100 graphics, while the i7-860 has none. Sockets differ: Intel BGA 1168 versus Intel Socket 1156. The launch MSRP for the i3-5157U is $315, while the i7-860 has no launch MSRP listed.

The Verdict

The data is unambiguous: the Intel Core i7-860 is the faster processor in every benchmark measured. It wins all five head-to-head tests by margins of 14.3% to 14.5%, covering both single-core and multi-core workloads. Its 4 cores, 8 threads, and 8 MB of L3 cache give it a structural advantage that the i3-5157U cannot overcome despite its newer 14 nm process. The i7-860 also has a higher base clock and the only boost clock in this comparison, making it the better choice for any CPU-bound task.

However, the i3-5157U is not without reason to exist. Its 28W TDP makes it suitable for mobile systems, and its integrated Intel Iris 6100 graphics eliminate the need for a discrete GPU. Its average benchmark score of 877 is close enough to the i7-860's 886 that in real-world use, the difference may be less noticeable than the benchmark gaps suggest. The i3-5157U also has a memory bandwidth figure of 29.9 GB/s, which the i7-860 lacks entirely.

For a builder choosing between these two, the decision hinges on platform. If you need a desktop processor with raw compute power and already have a graphics card, the i7-860 is the clear winner based on its 14.4% average lead across Cinebench tests. If you need a low-power mobile chip with built-in graphics, the i3-5157U is the only option that fits, and its performance is within 1% of the i7-860 on average. The i7-860's percentile of 24 versus the i3-5157U's 23 reflects their near-identical standing among all CPUs, but the i7-860 is the one that wins where it matters in this direct comparison.