Intel Core i5-7640X vs Intel Core i7-8559U Comparison

The benchmark data presents a clear split between two Intel Kaby Lake processors from different eras and market segments. The Intel Core i7-8559U, a mobile part, wins the majority of compute benchmarks, while the Intel Core i5-7640X, a desktop part, dominates in Geekbench tests. The outcome is not a simple victory for either, but a lesson in how different workloads interact with thread counts and clock speeds.

Where Each One Wins

The Intel Core i7-8559U is the decisive winner in Cinebench workloads. Across all three versions of the test (R15, R20, and R23), the i7-8559U outperforms the i5-7640X by a consistent margin. In multi-core tests, the i7-8559U leads by 15.8% in R15, R20, and R23, with scores of 703 versus 607, 2933 versus 2533, and 6984 versus 6031 respectively. The single-core results follow the same pattern: the i7-8559U wins by 16.5% in R15 (99 versus 85), by 16% in R20 (414 versus 357), and by 15.9% in R23 (986 versus 851). This consistency suggests the i7-8559U's architecture, specifically its 8 threads versus the i5-7640X's 4 threads, provides a structural advantage in rendering and 3D modeling tasks that Cinebench measures.

The Intel Core i5-7640X, however, finds its strength in Geekbench tests. It wins Geekbench multi-core by 16.4% with a score of 5137 versus 4293 for the i7-8559U. The single-core Geekbench test shows an even larger lead of 20.3%, with the i5-7640X scoring 1736 against 1384 for the i7-8559U. These results indicate that the i5-7640X excels in workloads that favor higher base clock speeds (3.90 GHz versus 2.70 GHz) and lower thread overhead, such as certain productivity applications, web browsing, and general system responsiveness. The data shows a clear split: Cinebench favors the i7-8559U, and Geekbench favors the i5-7640X.

The Verdict

The choice between these two processors depends entirely on the intended use case, and the benchmark data provides the only evidence needed for this decision. For users whose primary workload is content creation, 3D rendering, or any task that scales with thread count, the Intel Core i7-8559U is the clear selection. Its 8 threads enable it to finish Cinebench multi-core tests approximately 15.8% faster than the i5-7640X across all versions, a significant and repeatable advantage. The i7-8559U also leads in single-core Cinebench tests, which are less dependent on thread count, by margins between 15.9% and 16.5%, meaning its per-core efficiency is superior in this specific benchmark suite.

Conversely, for users who prioritize raw single-threaded performance in general-purpose applications, or who run software that does not utilize more than four threads, the Intel Core i5-7640X is the better option. Its Geekbench single-core score of 1736 is 20.3% higher than the i7-8559U's 1384, and its multi-core Geekbench score of 5137 is 16.4% higher than 4293. The i5-7640X also offers an unlocked multiplier, which suggests a potential for overclocking that the i7-8559U, with its locked multiplier, cannot match. The average benchmark scores reflect this split: the i7-8559U averages 2225, and the i5-7640X averages 2167, but this aggregate number obscures the distinct performance profiles. Both processors sit at the 47th percentile among all CPUs, meaning they are statistically equivalent in overall standing, but the path to that standing is very different.

Head-to-Head Benchmarks

The most decisive wins for the Intel Core i7-8559U occur in Cinebench R23 multi-core, where it scores 6984 against the i5-7640X's 6031, a 15.8% advantage. This is the largest absolute point difference in the Cinebench suite. The Cinebench R15 single-core test shows the highest percentage win for the i7-8559U at 16.5%, with scores of 99 versus 85. The i7-8559U's wins in Cinebench R20 and R15 multi-core tests are also notable, at 2933 versus 2533 and 703 versus 607 respectively, both maintaining the 15.8% delta. These consistent margins across different Cinebench versions indicate a stable architectural advantage that is not an artifact of a single test version.

The Intel Core i5-7640X's largest win is in Geekbench single-core, where it scores 1736 versus 1384 for the i7-8559U, a 20.3% lead. This is the highest delta percentage in the entire head-to-head comparison. Its Geekbench multi-core win is also substantial: 5137 versus 4293, a 16.4% advantage. These two wins for the i5-7640X are significant enough to offset its six losses in the Cinebench suite when considering overall average scores. The data shows that the i5-7640X's wins are larger in percentage terms (20.3% and 16.4%) than the i7-8559U's typical win margin (15.8% to 16.5%), but the i7-8559U secures victories in more test categories. The final tally of wins is 6 for the i7-8559U and 2 for the i5-7640X.

FAQ

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

A: The Intel Core i7-8559U is faster, scoring 6984 compared to 6031 for the Intel Core i5-7640X, a 15.8% difference.

Q: What is the largest performance gap between the two processors in any test?

A: The largest gap is in Geekbench single-core, where the Intel Core i5-7640X scores 1736, which is 20.3% higher than the Intel Core i7-8559U's score of 1384.

Q: Does the Intel Core i5-7640X win any multi-core tests?

A: Yes, it wins Geekbench multi-core with a score of 5137, which is 16.4% higher than the Intel Core i7-8559U's score of 4293.

Q: How many benchmark tests does each processor win?

A: The Intel Core i7-8559U wins 6 tests, and the Intel Core i5-7640X wins 2 tests.

Q: What are the average benchmark scores for each processor?

A: The Intel Core i7-8559U has an average benchmark score of 2225, and the Intel Core i5-7640X has an average benchmark score of 2167.

Q: Which processor has a higher base clock speed?

A: The Intel Core i5-7640X has a higher base clock speed of 3.90 GHz, compared to the 2.70 GHz base clock of the Intel Core i7-8559U.

Architecture Differences

Both processors are built on the Kaby Lake architecture and use a 14 nm process node, but they diverge significantly in their design intent. The Intel Core i7-8559U carries the codename Kaby Lake-R and is part of the Core i7 (Kaby Lake-U Refresh) generation. It features 4 cores and 8 threads, which enables simultaneous multithreading for improved parallel processing. Its cache hierarchy includes 64 KB of L1 per core, 256 KB of L2 per core, and 8 MB of shared L3 cache. This processor includes integrated Iris Pro Plus graphics, making it a self-contained solution for mobile systems. It operates on a 28 W TDP and fits the Intel BGA 1356 socket, which is a soldered, non-upgradeable platform.

The Intel Core i5-7640X, in contrast, is a desktop part from the Core i5 (X-Series 7th Gen) family, with the codename Kaby Lake-X. It has 4 cores and 4 threads, meaning it lacks hyper-threading and processes one thread per core. Its cache configuration is 64 KB of L1 per core, 256 KB of L2 per core, and a smaller 6 MB of shared L3 cache. The i5-7640X has no integrated graphics, requiring a discrete GPU for any display output. It uses the Intel Socket 2066 platform, which is designed for high-end desktop systems. The TDP is 112 W, reflecting the higher power envelope of a desktop processor. The i5-7640X also has an unlocked multiplier, allowing for overclocking, while the i7-8559U's multiplier is locked. The die size for the i7-8559U is 123 mm², while the i5-7640X's die size is not recorded.

Specification Differences

The two processors differ across several key specification fields. The Intel Core i7-8559U has 8 threads, while the Intel Core i5-7640X has 4 threads. The base clock of the i7-8559U is 2.70 GHz, and the i5-7640X has a base clock of 3.90 GHz. The boost clock is closer: the i7-8559U boosts to 4.50 GHz, and the i5-7640X boosts to 4.30 GHz. The TDP is a major differentiator, with the i7-8559U at 28 W and the i5-7640X at 112 W. Their sockets are incompatible: the i7-8559U uses Intel BGA 1356, and the i5-7640X uses Intel Socket 2066. The shared L3 cache is 8 MB for the i7-8559U and 6 MB for the i5-7640X. The i7-8559U includes integrated Iris Pro Plus graphics, whereas the i5-7640X has no integrated graphics. The i7-8559U has a locked multiplier, but the i5-7640X has an unlocked multiplier. The market segments differ, with the i7-8559U classified as Mobile and the i5-7640X as Desktop. The i5-7640X supports quad-channel memory and PCIe Gen 3, while the i7-8559U's memory bus and PCIe configuration are not specified in the data. The release dates are also different: the i7-8559U was released on 2018-04-04, and the i5-7640X was released on 2017-06-25.