Intel Core i5-8250U vs Intel Core i7-8650U Comparison

FAQ

Q: What is the core and thread configuration of these two processors?

A: Both the Intel Core i7-8650U and the Intel Core i5-8250U have 4 cores and 8 threads, making them identical in terms of parallel processing capacity.

Q: How do their clock speeds differ?

A: The i7-8650U has a base clock of 1900.00 MHz and a boost clock of 4.20 GHz, while the i5-8250U operates at a base clock of 1600.00 MHz and a boost clock of 3.40 GHz. The i7 has a 300 MHz higher base and an 800 MHz higher boost.

Q: Which processor has a larger L3 cache?

A: The i7-8650U features 8 MB of shared L3 cache, whereas the i5-8250U has 6 MB of shared L3 cache. The i7 offers 2 MB more.

Q: Are there any architectural differences between the two?

A: No, they share the same Kaby Lake architecture, Kaby Lake-R codename, 14 nm process node, and Intel BGA 1356 socket. Both are from the Kaby Lake-U Refresh generation.

Q: What do the benchmark scores indicate about their performance gap?

A: Across all 17 head-to-head benchmarks, the i7-8650U wins every single test. The average benchmark score for the i7 is 8932, compared to 8577 for the i5, a difference of roughly 4.1%.

Q: Which processor has a higher percentile ranking?

A: The i7-8650U sits at the 65th percentile among all CPUs, while the i5-8250U is at the 64th percentile. This indicates both are mid-range performers, with the i7 having a slight edge.

Architecture Differences

The two processors are built on the same fundamental architecture. Both use the Kaby Lake architecture with the Kaby Lake-R codename, fabricated on Intel's 14 nm process node. The die size is identical at 123 mm², and both use the Intel BGA 1356 socket. The foundry is Intel for both, and neither supports ECC memory. The integrated graphics are the same, UHD 620.

The key differences lie in the core-level specifications and cache allocation. The i7-8650U has a base clock of 1900.00 MHz and a boost clock of 4.20 GHz, while the i5-8250U has a base clock of 1600.00 MHz and a boost clock of 3.40 GHz. This means the i7 can reach a peak frequency that is 0.80 GHz higher, which directly impacts single-threaded performance.

Cache configurations differ as well. Both have 64 KB of L1 cache per core and 256 KB of L2 cache per core, but the shared L3 cache is 8 MB on the i7 versus 6 MB on the i5. This 2 MB difference can affect how much data can be stored closer to the cores, potentially reducing latency for frequently accessed data in multi-threaded workloads.

The generation labeling is also distinct. The i7 is listed as "Core i7 (Kaby Lake-U Refresh)" while the i5 is "Core i5 (Kaby Lake-U Refresh)". Both were released on the same date, 2017-08-20, and both have their multiplier locked, meaning no overclocking is supported. The part numbers differ, with the i7 using SR3L8 and the i5 using SR3LA.

Head-to-Head Benchmarks

The data is unambiguous: the i7-8650U wins all 17 recorded head-to-head benchmark comparisons. The largest margin comes in the passmark_find_prime_numbers test, where the i7 scores 22 against the i5's 18, a delta of 22.2%. This suggests the i7's higher boost clock significantly accelerates integer-heavy prime number generation.

In Cinebench tests, the i7 maintains a consistent advantage. For Cinebench R15 multi-core, the i7 scores 529 versus 495, a 6.9% lead. Single-core R15 shows 74 against 69, a 7.2% advantage. The R20 multi-core test shows 2206 versus 2065 (6.8% lead), and R20 single-core shows 311 versus 291 (6.9%). The R23 multi-core test has the i7 at 5253 and the i5 at 4918, a 6.8% gap, while R23 single-core shows 741 versus 694, also 6.8%.

PassMark tests reveal a varied picture. The data compression test shows the i7 at 78936 versus 76521, a 3.2% lead. Data encryption shows 2067 versus 1979, a 4.4% advantage. Extended instructions are close, with 5042 versus 4920, a 2.5% delta. Floating point math shows 13299 versus 12706, a 4.7% lead, while integer math shows 22007 versus 20885, a 5.4% advantage.

The physics test is another notable outlier. The i7 scores 472, while the i5 manages 405, a 16.5% delta. This is a substantial gap that suggests the i7's clock advantage is particularly impactful in physics simulations. The multithread test shows 6193 versus 5812, a 6.6% lead. Random string sorting shows 10485 versus 10257, a 2.2% delta, and single-thread tests show 2103 versus 1886, an 11.5% advantage for the i7.

Specification Differences

The following fields differ between the two processors:

• Base Clock: i7-8650U at 1900.00 MHz, i5-8250U at 1600.00 MHz.
• Boost Clock: i7-8650U at 4.20 GHz, i5-8250U at 3.40 GHz.
• L3 Cache: i7-8650U has 8 MB shared, i5-8250U has 6 MB shared.
• Generation: i7-8650U is Core i7 (Kaby Lake-U Refresh), i5-8250U is Core i5 (Kaby Lake-U Refresh).
• Part Number: i7-8650U uses SR3L8, i5-8250U uses SR3LA.
• Average Benchmark Score: i7-8650U scores 8932, i5-8250U scores 8577.
• Percentile vs All CPUs: i7-8650U is at the 65th percentile, i5-8250U at the 64th.

All other specifications are identical: 4 cores, 8 threads, 15 W TDP, Intel BGA 1356 socket, Kaby Lake architecture, Kaby Lake-R codename, 14 nm process node, 123 mm² die size, 64 KB L1 per core, 256 KB L2 per core, DDR4 memory support, no ECC, UHD 620 integrated graphics, mobile market segment, active production status, same release date, no unlocked multiplier, and no launch MSRP listed.

Where Each One Wins

The i7-8650U wins in every single benchmark category recorded. There is no test in the database where the i5-8250U comes out ahead. This makes the use-case split straightforward, but the degree of advantage varies by workload.

For tasks that rely heavily on single-thread performance, the i7 is clearly superior. The passmark_single_thread test shows an 11.5% advantage, and Cinebench single-core tests all show around 6.8% to 7.2% leads. This suggests the i7 is better for applications like web browsing, office productivity, and lightly-threaded software where clock speed matters most.

For multi-threaded workloads, the i7 also leads, but the margins are slightly smaller in some cases. Cinebench multi-core tests show 6.8% to 6.9% advantages, while the passmark_multithread test shows a 6.6% delta. However, the physics test shows a 16.5% lead, and the prime numbers test shows a 22.2% lead, indicating that certain computational workloads benefit disproportionately from the i7's higher clocks and larger cache.

The data compression and encryption tests show smaller margins, at 3.2% and 4.4% respectively, suggesting that these workloads are less sensitive to clock speed differences. The extended instructions test has the smallest delta at 2.5%, indicating that SIMD-heavy code sees the least benefit from the i7's advantages.

The Verdict

Based strictly on the recorded data, the Intel Core i7-8650U is the superior processor in every measurable way. It wins all 17 head-to-head benchmarks, has a higher average benchmark score (8932 versus 8577), and sits at a higher percentile (65th versus 64th). The i7's higher base and boost clocks, combined with its larger 8 MB L3 cache, provide consistent advantages across both single-threaded and multi-threaded workloads.

The i5-8250U is not a poor performer; its average score of 8577 places it in the same general performance tier, and its 64th percentile ranking is only one point lower than the i7's 65th. For users who are not pushing their processor to the limit, the i5 would deliver similar real-world experiences in many scenarios, particularly in workloads where the performance delta is small, such as extended instructions (2.5%) or random string sorting (2.2%).

However, for applications that demand maximum performance, whether it is prime number calculations (22.2% lead), physics simulations (16.5% lead), or single-thread responsiveness (11.5% lead), the i7-8650U is the clear choice. The data indicates that the i7's higher boost clock of 4.20 GHz versus 3.40 GHz is the primary driver of these gains, and the extra 2 MB of L3 cache may help in cache-sensitive workloads.

The choice comes down to whether the user needs the extra performance headroom. The i5-8250U is adequate for basic tasks, but the i7-8650U provides a measurable, consistent uplift across the board. If the workload involves any of the tests where the i7 excels by double-digit percentages, the i7 is the only rational pick. For casual use, either processor would suffice, but the data clearly favors the i7-8650U as the more capable part.