Intel Core i3-8100 vs Intel Core i7-8550U Comparison

Where Each One Wins

The Intel Core i7-8550U and Intel Core i3-8100 present a clear split in workload character, despite both being 4-core parts. The recorded data shows the i7-8550U takes 8 benchmark wins, while the i3-8100 takes 9, but the margins and categories tell a more nuanced story than the raw count suggests.

The i7-8550U dominates every Cinebench test in the database. Across Cinebench R15, R20, and R23, both single-core and multi-core, the mobile part wins with deltas between 30.2% and 30.9%. That is a sweeping, consistent advantage in rendering workloads. It also wins PassMark integer math by 28.3% and data encryption by 6.3%. These are workloads that respond strongly to simultaneous multithreading and higher peak clocks under boost.

The i3-8100, meanwhile, wins the PassMark suite more broadly but with smaller margins. It takes data compression by 10.6%, floating point math by 9.1%, single-thread by 8.3%, extended instructions by 35.3%, and prime numbers by 18.5%. The multithread score goes to the desktop part with a modest 4.1% edge, and physics and random string sorting are also its wins at 2.4% each. The extended instructions result is the largest single margin in either direction, a decisive win for the i3-8100.

In short, the i7-8550U is the clear choice for threaded rendering and integer-heavy tasks, while the i3-8100 holds the edge in most PassMark utility workloads, especially those leveraging extended instruction sets. The two chips are close in overall average benchmark score: the i7-8550U sits at 8407, the i3-8100 at 8123, a difference of roughly 3.5% in favor of the mobile part.

Architecture Differences

The two processors come from different Intel families and target different physical environments. The i7-8550U is a Kaby Lake-R part on a 14 nm process, built for mobile with a 15 W TDP and an Intel BGA 1356 socket. The i3-8100 is Coffee Lake, also 14 nm, but designed for desktop with a 65 W TDP and an Intel Socket 1151. The die sizes are close: 123 mm² for the i7-8550U, 126 mm² for the i3-8100.

Core counts match at 4, but threading differs. The i7-8550U supports 8 threads, the i3-8100 only 4. Base clocks are very different: the i7-8550U runs at 1800 MHz, while the i3-8100 runs at 3600 MHz. The i7-8550U can boost to 4.00 GHz, while the i3-8100 has no boost clock listed, meaning it relies entirely on its higher base frequency. The mobile chip uses that boost headroom to compensate for its low base clock, while the desktop chip maintains a constant frequency.

Cache hierarchies differ as well. Both have 64 KB L1 and 256 KB L2 per core, but the i7-8550U has 8 MB of shared L3, while the i3-8100 has 6 MB. That extra 2 MB of L3 likely helps the i7-8550U in the threaded rendering tests. Both support DDR4 memory, but the i3-8100 lists dual-channel support with 38.4 GB/s bandwidth, while the i7-8550U does not list a memory bus or bandwidth figure. The i3-8100 also supports ECC memory, which the i7-8550U does not, and lists PCIe Gen 3 with 16 lanes (CPU only), while the i7-8550U does not list PCIe details.

Integrated graphics differ: the i7-8550U carries UHD 620, the i3-8100 carries UHD Graphics 630. In terms of production status, the i7-8550U remains active, while the i3-8100 is end-of-life. The i7-8550U launched on 2017-08-20, the i3-8100 on 2017-10-04. Neither chip has an unlocked multiplier. The i3-8100 has a launch MSRP of $117, while the i7-8550U has no listed launch MSRP.

Head-to-Head Benchmarks

The Cinebench results are the i7-8550U's strongest statement. In Cinebench R15 multi-core, it scores 496 versus 379, a 30.9% lead. Single-core R15 shows 69 versus 53, a 30.2% lead. These margins repeat across R20 and R23. In R20 multi-core, the i7-8550U scores 2068 against 1582, a 30.7% lead; single-core is 291 against 223, a 30.5% lead. In R23 multi-core, it is 4926 against 3769, a 30.7% lead; single-core is 695 against 532, a 30.6% lead. The consistency is striking: every Cinebench variant, every mode, lands within a narrow band of 30.2% to 30.9%. This indicates a structural advantage, not a workload-specific quirk.

PassMark integer math follows the same pattern. The i7-8550U scores 20770 against 16191, a 28.3% win. Data encryption goes to the i7-8550U at 1944 against 1828, a 6.3% margin. These wins align with the extra threads: workloads that scale with thread count see the i7-8550U pull ahead.

The i3-8100 answers in the PassMark suite. Extended instructions is its biggest victory: 7212 versus 4665, a 35.3% margin. That is the largest delta in the entire comparison. Find prime numbers goes to the i3-8100 at 27 versus 22, an 18.5% lead. Data compression is 82992 versus 74223, a 10.6% win. Floating point math is 13774 versus 12523, a 9.1% edge. Single-thread performance favors the i3-8100 at 2203 versus 2021, an 8.3% lead in both single-thread listings. Multithread goes to the i3-8100 at 6086 versus 5835, a 4.1% margin, despite the i7-8550U having twice the thread count. Physics is 462 versus 451, a 2.4% win, and random string sorting is 10150 versus 9902, also a 2.4% win.

The pattern is clear. The i7-8550U wins where thread scaling and boost clocks matter. The i3-8100 wins where sustained frequency and instruction-level efficiency matter. The i3-8100's 3600 MHz base clock, double the i7-8550U's 1800 MHz, appears to be the deciding factor in the PassMark workloads that do not scale cleanly with threads.

The Verdict

The data points to a simple rule: pick the i7-8550U if the workload is threaded rendering or integer-heavy computation. Every Cinebench test, from R15 to R23, shows a consistent 30% advantage. The extra threads and 4.00 GHz boost clock deliver a decisive edge in these scenarios. The integer math result, a 28.3% win, reinforces this.

Pick the i3-8100 if the workload involves extended instructions, data compression, floating point math, or single-threaded tasks. Its 35.3% lead in extended instructions is the largest margin in the comparison. Its 10.6% win in data compression and 8.3% win in single-thread performance show that the higher base clock of 3600 MHz matters in applications that do not benefit from simultaneous multithreading.

The average benchmark scores are close: 8407 for the i7-8550U, 8123 for the i3-8100, with the i7-8550U ahead by about 3.5%. Both chips sit at the 64th percentile of all CPUs in the database. The i7-8550U's nearest rivals include the Intel Xeon Gold 5318N at 8433 (0.3% ahead) and the Intel Core i5-10210U at 8344 (0.7% behind). The i3-8100's nearest rivals include the AMD EPYC 7302 at 8139 (0.2% ahead) and the Intel Xeon Gold 5318Y at 8147 (0.3% ahead). These rival comparisons show both chips are positioned in a dense performance cluster, where small percentage differences separate many parts.

For a mobile platform, the i7-8550U offers the obvious advantage of 15 W TDP and BGA 1356 mounting. For a desktop platform, the i3-8100 offers 65 W TDP, Socket 1151, ECC memory support, and a launch MSRP of $117. The production status also matters: the i7-8550U is active, while the i3-8100 is end-of-life. From the recorded data alone, the i7-8550U is the stronger overall performer, but the i3-8100 is the better fit for specific utility workloads and desktop use cases.

FAQ

Q: Which processor is faster in Cinebench R23 multi-core?

A: The Intel Core i7-8550U scores 4926, while the Intel Core i3-8100 scores 3769, a 30.7% advantage for the i7-8550U.

Q: Does the i3-8100 ever beat the i7-8550U by a large margin?

A: Yes. In PassMark extended instructions, the i3-8100 scores 7212 against 4665, a 35.3% lead, the largest single delta in the comparison.

Q: Why does the i7-8550U win Cinebench despite a much lower base clock?

A: The i7-8550U has 8 threads versus 4, an 8 MB shared L3 cache versus 6 MB, and a boost clock of 4.00 GHz. These factors combine to deliver consistent 30% wins across all Cinebench versions.

Q: Which chip has better single-thread performance?

A: The i3-8100. It scores 2203 in PassMark single-thread, while the i7-8550U scores 2021, an 8.3% advantage for the desktop part.

Q: Do both chips support ECC memory?

A: No. The i3-8100 supports ECC memory, while the i7-8550U does not.

Q: What is the average benchmark score difference between the two?

A: The i7-8550U has an average benchmark score of 8407, while the i3-8100 has 8123, a difference of about 3.5% in favor of the i7-8550U. Both sit at the 64th percentile of all CPUs.