Intel Core i7-5550U vs Intel Core i7-870S Comparison

The Intel Core i7-5550U and the Intel Core i7-870S represent two very different design philosophies from Intel, separated by nearly five years of architectural evolution. The 5550U is a low-power mobile part built for efficiency, while the 870S is a higher-power desktop chip from the Nehalem era. Benchmark data shows a surprisingly tight contest, with the newer mobile processor edging out the older desktop part in every single head-to-head test, despite having half the physical cores.

Head-to-Head Benchmarks

The head-to-head results are remarkably consistent, showing the Core i7-5550U winning all five Cinebench comparisons, albeit by narrow margins. In Cinebench R15 multicore, the 5550U scores 238 against the 870S’s 236, a 0.8% delta. This is the largest single advantage the mobile chip secures. The pattern continues in Cinebench R20 multicore, where the 5550U posts 992 versus 987, a 0.5% lead. The R23 multicore test shows the same story: 2363 for the 5550U and 2350 for the 870S, a 0.6% gap.

Single-core performance is just as close. In Cinebench R20 singlecore, both processors score exactly 139, resulting in a 0% delta. The R23 singlecore test sees the 5550U ahead at 333 versus 331, a 0.6% margin. The data indicates that the 5550U’s architectural efficiency from the Broadwell generation fully compensates for its disadvantage in core count and raw clock speed.

The average benchmark scores corroborate these head-to-head findings. The 5550U holds an average benchmark score of 813, while the 870S trails at 809. This places both processors in the 22nd percentile of all CPUs, indicating they are closely matched in overall performance. In terms of nearest rivals, the 5550U sits 0.5% above the AMD A10-6800K (score 809) and is exactly tied with the Intel Core 2 Extreme QX9775 (score 813). The 870S, meanwhile, is exactly tied with that same AMD A10-6800K at 809 and sits 0.4% above the AMD Athlon X4 850 and Intel Xeon X5482, both scoring 805.

Architecture Differences

The architectural divide between these two chips is substantial. The Core i7-5550U is built on Intel’s 14 nm process node, while the Core i7-870S uses the much older 45 nm node. This explains the dramatic difference in transistor count: the 5550U packs 1,900 million transistors into a 133 mm² die, whereas the 870S contains just 774 million transistors on a much larger 296 mm² die. The newer process allows the 5550U to achieve higher efficiency with fewer resources.

The core configurations differ fundamentally. The 5550U has 2 cores and 4 threads, while the 870S has 4 cores and 8 threads. Despite this 2x advantage in core count for the older chip, the 5550U still wins in multi-threaded workloads, highlighting the superior per-core performance of the Broadwell architecture. Cache hierarchies also differ: both share 64 KB L1 and 256 KB L2 per core, but the 5550U has 4 MB of shared L3 cache, while the 870S doubles that to 8 MB.

Clock speeds favor the 870S. It runs at a 2.67 GHz base clock with a 3.60 GHz boost, compared to the 5550U’s 2.00 GHz base and 3.00 GHz boost. The 870S compensates for its older architecture with higher frequencies, yet still loses. The integrated graphics situation is reversed: the 5550U includes Intel HD 6000 graphics, while the 870S has no integrated graphics at all. Memory support is DDR3 for both with dual-channel buses, though the 5550U lists a memory bandwidth of 29.9 GB/s while the 870S does not specify a bandwidth figure.

FAQ

Q: Which processor has more physical cores?

A: The Intel Core i7-870S has 4 cores and 8 threads, doubling the Core i7-5550U’s 2 cores and 4 threads.

Q: How much faster is the Core i7-5550U in multi-core Cinebench R23?

A: The 5550U scores 2363, which is 0.6% ahead of the 870S’s 2350 in the Cinebench R23 multicore test.

Q: Are there any benchmark tests where the two processors tie?

A: Yes, in Cinebench R20 singlecore, both the 5550U and the 870S score exactly 139, resulting in a 0% delta.

Q: Which chip has a smaller manufacturing process node?

A: The Core i7-5550U uses a 14 nm process, while the Core i7-870S uses a 45 nm process, making the 5550U the more advanced node.

Q: What is the launch MSRP of the Core i7-5550U?

A: The Core i7-5550U has a launch MSRP of $426. The Core i7-870S does not have a listed launch MSRP in the data.

Q: Do both processors support ECC memory?

A: No, neither the Core i7-5550U nor the Core i7-870S supports ECC memory.

Specification Differences

The two processors differ across nearly every specification field. The core and thread counts are the most obvious divergence: 2 cores and 4 threads for the 5550U versus 4 cores and 8 threads for the 870S. Base clock speeds differ significantly, with the 870S at 2.67 GHz compared to the 5550U’s 2.00 GHz. Boost clocks show a similar gap: 3.60 GHz for the 870S versus 3.00 GHz for the 5550U.

Thermal design power is a stark differentiator. The 5550U draws only 15 W, while the 870S consumes 82 W, making the mobile chip over five times more power-efficient on paper. Socket compatibility is entirely different: the 5550U uses Intel BGA 1168, while the 870S uses Intel Socket 1156. The architectures are from separate eras: Broadwell-U for the 5550U and Nehalem (Lynnfield) for the 870S.

Process technology and die size differ dramatically, as do transistor counts. The 5550U’s 14 nm node and 133 mm² die contrast with the 870S’s 45 nm node and 296 mm² die. L3 cache is 4 MB on the 5550U versus 8 MB on the 870S. PCIe support varies: the 5550U offers 12 Gen 2 lanes, while the 870S offers 16 Gen 2 lanes. The 5550U includes integrated Intel HD 6000 graphics; the 870S has none. Market segments differ (Mobile versus Desktop), and release dates are years apart: 2015 for the 5550U, 2010 for the 870S.

Where Each One Wins

The Core i7-5550U wins in every benchmark category measured. Its victories are narrow but consistent across all Cinebench tests, including both single-core and multi-core workloads. The data shows it holds a 0.8% lead in Cinebench R15 multicore and a 0.6% lead in Cinebench R23 multicore. It also matches or slightly exceeds the 870S in single-core tests, making it the better performer for both lightly-threaded and heavily-threaded applications.

The Core i7-870S does not win any benchmark comparisons in this dataset. However, the specification sheet points to areas where it could theoretically excel in different circumstances. It has double the L3 cache (8 MB versus 4 MB) and a higher boost clock (3.60 GHz versus 3.00 GHz). These attributes suggest it might handle cache-sensitive workloads or bursty single-threaded tasks better, but the measured Cinebench results do not support this hypothesis. The 870S also has more PCIe lanes (16 versus 12), which could benefit expansion-heavy desktop configurations.

The 5550U’s wins are particularly notable given its power envelope. A 15 W processor beating an 82 W desktop chip in multi-threaded tests underscores the efficiency gains of the newer architecture. For mobile users, the 5550U offers the clear advantage of integrated graphics, eliminating the need for a discrete GPU in basic systems.

The Verdict

Benchmark data points decisively to the Intel Core i7-5550U as the superior processor. It wins all five head-to-head Cinebench tests, holds a higher average benchmark score (813 versus 809), and achieves these results while consuming only 15 W of power compared to the 870S’s 82 W. The 5550U also includes integrated graphics, a feature entirely absent from the 870S. Its 14 nm process node and higher transistor density (1,900 million versus 774 million) give it a clear architectural advantage that overcomes its lower core count and clock speeds.

The Core i7-870S should only be considered by users with a specific need for its particular characteristics. It offers 8 MB of L3 cache and a 3.60 GHz boost clock, which might appeal in niche scenarios, but these do not translate into benchmark wins. Its 4-core, 8-thread configuration is theoretically more capable for parallel workloads, yet the data shows the 2-core 5550U outperforms it in multicore tests. The 870S’s desktop socket (Intel Socket 1156) might be preferable for those with existing motherboards, but its higher power draw and older architecture make it a less compelling choice.

For anyone choosing between these two, the Core i7-5550U is the clear pick based on performance, efficiency, and feature set. It delivers equal or better scores in every measured test while using a fraction of the power. The 870S represents older technology that, despite its higher core count and clock speeds, cannot match the architectural efficiency of the newer Broadwell design. The 5550U’s 22nd percentile ranking and average score of 813 place it at the same performance tier as the 870S, but with substantial efficiency advantages and a more modern feature set.