Intel Core i5-8250U vs Intel Core i7-8550U Comparison

These two 15-watt Kaby Lake-R processors share a platform, a core count, and a release date, but the benchmark data reveals a more nuanced relationship than their similar specifications might suggest. The i7-8550U wins more individual tests, but the i5-8250U takes several meaningful victories in specific workloads, making the choice less about raw performance and more about what you plan to do with the laptop. Neither chip holds a decisive overall lead, and the data shows a near-total performance parity that will surprise anyone expecting the i7 to be categorically faster.

Head-to-Head Benchmarks

The most striking finding is how close these two chips are on multi-core workloads. In Cinebench R15 multi-core, the i7-8550U scores 496 against the i5-8250U’s 495, a difference of just 0.2%. The gap widens only slightly in Cinebench R20 multi-core, where the i7 posts 2068 versus 2065 (0.1% ahead), and in Cinebench R23 multi-core, the i7’s 4926 edges out the i5’s 4918 by 0.2%. These are effectively identical results, indicating that sustained multi-threaded performance is dictated more by the shared 15-watt thermal envelope than by any architectural advantage.

Single-core results follow the same pattern. Cinebench R15 single-core scores are exactly tied at 69, and Cinebench R20 single-core is also a dead heat at 291. The i7 only manages a 1-point lead in Cinebench R23 single-core, 695 versus 694, a 0.1% margin that is statistically meaningless. This is surprising given the i7’s higher boost clock, but the data shows no real-world single-threaded Cinebench advantage.

The PassMark suite tells a different story, with the i5-8250U actually winning the majority of the compute tests. The i5 takes data compression by a solid 3.1%, scoring 76521 against the i7’s 74223. It also wins data encryption (1979 vs 1944, a 1.8% lead), extended instructions (4920 vs 4665, a 5.5% margin), floating point math (12706 vs 12523, 1.5% ahead), integer math (20885 vs 20770, 0.6% ahead), and random string sorting (10257 vs 9902, a 3.6% advantage). These are not trivial margins; the extended instructions win of 5.5% is the largest positive delta for either chip in the entire head-to-head.

The i7-8550U’s wins are concentrated in specific areas. Its largest victory is in PassMark find prime numbers, where it scores 22 versus the i5’s 18 — an 18.2% advantage that is the most lopsided result on the entire list. It also wins PassMark physics by a notable 10.2% (451 vs 405), and PassMark single-thread by 6.7% (2021 vs 1886). The i7’s PassMark multithread score of 5835 is only 0.4% ahead of the i5’s 5812, a negligible difference. Overall, the i7 wins 9 of the 17 head-to-head tests, but the i5 wins 8, and the aggregate scores reflect this near-tie: the i5’s average benchmark score is 8577 against the i7’s 8407. Both chips sit at the 64th percentile of all CPUs.

Where Each One Wins

The i5-8250U is the better choice for workloads that stress the memory subsystem and integer/fixed-point operations. The data shows consistent wins in data compression, encryption, and sorting — all tasks that rely heavily on cache efficiency and memory bandwidth. The 5.5% lead in extended instructions suggests the i5 handles SIMD-style workloads better in practice, despite identical architecture. If your daily driver involves file archiving, database work, or any application that spends time shuffling data around, the i5’s scores indicate it will finish those tasks measurably faster.

The i7-8550U wins where raw clock speed matters most. Its 6.7% lead in PassMark single-thread and 10.2% lead in physics point to better responsiveness in lightly-threaded, latency-sensitive applications. The 18.2% blowout in prime number calculation is a classic integer-heavy, branch-prediction-sensitive workload, and it suggests the i7’s higher boost clock provides a real benefit in such code. If you run spreadsheet recalculation, scripting, or any application that is bottlenecked by a single thread, the i7 will feel snappier. The i7 also edges out the i5 in every Cinebench multi-core test, so renderers and video encoders that scale across cores will show a tiny, though not transformative, preference for the i7.

FAQ

Q: Is the i7-8550U faster than the i5-8250U in multi-core rendering?

A: Marginally. In Cinebench R23 multi-core, the i7 scores 4926 versus the i5’s 4918, a 0.2% difference. Cinebench R20 multi-core shows the same pattern (2068 vs 2065), so the i7 is technically ahead but the advantage is within run-to-run variance.

Q: Which CPU has better single-thread performance?

A: The i7-8550U. Its PassMark single-thread score of 2021 is 6.7% higher than the i5’s 1886. However, Cinebench single-core scores are essentially tied, with both chips scoring 69 in R15 and 291 in R20.

Q: Why does the i5-8250U win so many PassMark tests?

A: The i5 wins data compression (76521 vs 74223), encryption (1979 vs 1944), and sorting (10257 vs 9902). These tests are sensitive to cache and memory behavior, and the i5’s results suggest it handles these workloads more efficiently despite having 2 MB less L3 cache.

Q: What is the largest performance gap between the two?

A: The biggest delta is in PassMark find prime numbers, where the i7-8550U scores 22 versus the i5’s 18, an 18.2% advantage for the i7. The i5’s largest win is 5.5% in extended instructions.

Q: Do these CPUs have the same integrated graphics?

A: Yes, both feature Intel UHD 620 graphics. There is no difference in the iGPU between the two.

Q: Which chip has a higher average benchmark score?

A: The i5-8250U has a higher average benchmark score of 8577, compared to the i7-8550U’s 8407. This is largely because the i5’s wins in PassMark tests are more numerous and substantial than the i7’s wins.

Specification Differences

The two processors share the same core and thread count (4 cores, 8 threads), the same 15-watt TDP, the same socket (Intel BGA 1356), and the same integrated graphics (UHD 620). The key differentiators are clock speeds and cache. The i7-8550U has a base clock of 1800 MHz and a boost clock of 4.00 GHz, while the i5-8250U runs at 1600 MHz base and 3.40 GHz boost. The i7 also carries 8 MB of shared L3 cache, whereas the i5 has 6 MB. Both have the same 64 KB L1 and 256 KB L2 per core, a 123 mm² die size, and DDR4 memory support. The part numbers differ (SR3LC for the i7, SR3LA for the i5), but both are built on the same 14 nm process at Intel’s foundry.

Architecture Differences

Both chips are built on the Kaby Lake architecture and use the Kaby Lake-R codename. They share the same 14 nm process node, 123 mm² die size, and DDR4 memory support. The architectural differences are limited to the L3 cache allocation (8 MB on the i7 versus 6 MB on the i5) and the clock speed bins. No other differences exist in the data: same socket, same core topology, same foundry, same memory type, and same integrated graphics. The i7 is essentially a higher-binned version of the same silicon, with a 200 MHz higher base clock and a 600 MHz higher boost clock, plus an extra 2 MB of L3 cache. Both are unlocked multipliers, meaning neither can be overclocked.

The Verdict

The data paints a clear picture: if you need the absolute best single-threaded performance and the fastest possible response in latency-sensitive tasks, the i7-8550U is the pick. Its 6.7% lead in PassMark single-thread and 10.2% in physics are the most meaningful advantages in the entire comparison, and the 18.2% win in prime number calculation shows it handles branch-heavy code significantly better. The 600 MHz boost clock advantage is real, and it shows up in the workloads that care about it.

However, the i5-8250U is the better all-rounder for mixed workloads. It wins more PassMark compute tests, including a 5.5% margin in extended instructions and a 3.1% margin in data compression, and it has a higher average benchmark score (8577 vs 8407). The i5’s wins are more numerous and cover more common tasks like encryption and sorting. For a typical user running office applications, browsing, and light content creation, the i5-8250U will deliver perfectly comparable performance at a lower tier price point, based on the benchmark evidence. The i7-8550U only makes sense if your specific workloads are those where it wins — primarily single-threaded applications and physics simulations. For everything else, the i5-8250U matches or beats it. The data does not support paying a premium for the i7 unless you know you need its specific strengths.