Intel Core i5-1135G7 vs Intel Core i5-8365U Comparison

The Intel Core i5-1135G7 and Intel Core i5-8365U are both 15-watt mobile processors with four cores and eight threads, but they represent two distinct generations of Intel laptop silicon. Benchmark data shows a decisive victory for the newer Tiger Lake part, which wins all 17 head-to-head comparisons against the Whiskey Lake-based i5-8365U. The average benchmark score gap is notable: the i5-1135G7 posts an average score of 9053 compared to 8708 for the i5-8365U, placing both in the 65th percentile of all CPUs. While the overall percentile is identical, the per-test deltas reveal where the newer architecture pulls ahead, and the specification differences explain why.

Where Each One Wins

The benchmark results are unambiguous: the Intel Core i5-1135G7 wins every single head-to-head test, with a 17-0 sweep. There is no workload category where the i5-8365U manages to outpace its successor. The largest victories for the i5-1135G7 come in encryption and prime-number finding, where it leads by 172.4% and 78.9% respectively. These are computationally intensive, latency-sensitive tasks that benefit heavily from the newer core design and larger caches.

For users prioritizing single-threaded responsiveness, the i5-1135G7 delivers a 27.4% advantage in PassMark single-thread performance, scoring 2640 versus 2073. This translates to snappier application launches and more responsive everyday computing. The multi-threaded picture is even more lopsided: the i5-1135G7 scores 9512 in PassMark multithread against 5976 for the i5-8365U, a 59.2% lead. This makes the Tiger Lake part the clear choice for any workload that can utilize all eight threads, such as video encoding, compilation, or heavy multitasking.

The i5-8365U does not claim a single victory, but its performance is not without context. It remains a capable processor for basic office tasks and light productivity, as evidenced by its PassMark integer math score of 22021 and floating-point score of 13110. However, the data suggests that anyone choosing between these two for a new system should strongly favor the i5-1135G7, as it offers superior performance across every measured dimension without any compensatory strengths in the older chip.

Architecture Differences

The fundamental architectural gap between these two processors is the process node and core design. The i5-1135G7 is built on Intel's 10 nm process and uses the Tiger Lake-U architecture with Willow Cove cores, while the i5-8365U uses the older 14 nm process with Whiskey Lake-U architecture. This node difference is a primary driver of the performance gap, as the newer process allows for higher efficiency and more transistors in a similar power envelope.

Cache hierarchies differ substantially. The i5-1135G7 has 80 KB of L1 cache per core, 1.25 MB of L2 per core, and 8 MB of shared L3 cache. The i5-8365U has 64 KB L1 per core, 256 KB L2 per core, and only 6 MB of shared L3. The larger caches on the Tiger Lake part, particularly the 1.25 MB per-core L2 versus 256 KB, explain much of its advantage in the PassMark data compression and random string sorting tests, where data locality and cache reuse are critical.

Integrated graphics are also a generation apart. The i5-1135G7 features Iris Xe Graphics G7 with 80 execution units, while the i5-8365U ships with the older UHD Graphics 620. This is a significant upgrade for the newer part, though the provided benchmarks do not directly test graphics performance. Memory support differs as well: the i5-1135G7 supports both DDR4 and LPDDR4X, while the i5-8365U is limited to DDR4. The i5-8365U has a specified memory bandwidth of 38.4 GB/s, while the i5-1135G7's bandwidth is not listed in the data.

PCIe connectivity also differs. The i5-1135G7 offers PCIe Gen 4 with 4 lanes (CPU only), whereas the i5-8365U provides PCIe Gen 3 with 16 lanes (CPU only). The newer part's Gen 4 support offers higher per-lane bandwidth, which can benefit fast NVMe SSDs, but the older part has more total lanes for expansion.

Head-to-Head Benchmarks

The Cinebench suite shows a remarkably consistent pattern. Across R15, R20, and R23, the i5-1135G7 leads by 56.6% in multi-core tests and 56.5-57.7% in single-core tests. Specifically, in Cinebench R23 multi-core, the i5-1135G7 scores 7909 versus 5050, while in single-core it scores 1116 versus 713. This consistency across versions indicates a fundamental per-clock advantage rather than a workload-specific quirk.

The PassMark suite reveals where the i5-1135G7's architectural improvements shine brightest. Data encryption shows a staggering 172.4% delta, with scores of 5465 versus 2006. This likely reflects the newer AES-NI implementation and improved cryptographic instruction handling in Willow Cove cores. Prime number finding also shows a large 78.9% gap (34 versus 19), which stresses integer throughput and branch prediction. Floating-point math shows a 46.6% advantage (19221 versus 13110), while integer math is 44.5% ahead (31814 versus 22021).

The smallest deltas are in random string sorting at 23.1% (12625 versus 10256) and single-thread performance at 27.4% (2640 versus 2073). Even these "small" gaps are substantial in real-world terms. The data compression test shows a 35.6% advantage (103380 versus 76239), and extended instructions show a 46% lead (7406 versus 5074). The physics test rounds out the results with a 36.7% delta (577 versus 422), and the overall multithread score shows a 59.2% advantage (9512 versus 5976).

Specification Differences

The two processors differ in several key specification fields. The i5-1135G7 has a base clock of 1500 MHz and a boost clock of 4.20 GHz, while the i5-8365U has a slightly higher base of 1600 MHz but a lower boost of 4.10 GHz. Both have a TDP of 15 watts. The socket differs: BGA 1449 for the i5-1135G7 versus BGA 1528 for the i5-8365U, meaning they are not pin-compatible.

The die size is listed only for the i5-1135G7 at 144 mm², while the i5-8365U's die size is not provided. The release dates show the i5-8365U launched in April 2019, while the i5-1135G7 followed in September 2020. The launch MSRP for the i5-1135G7 is $309, while the i5-8365U launched at $297. Both are end-of-life products with locked multipliers. The part numbers are SRK05 for the i5-1135G7 and SRF9Z for the i5-8365U.

Memory support is another differentiator: the i5-1135G7 supports both DDR4 and LPDDR4X, while the i5-8365U supports only DDR4. Both have dual-channel memory buses, but the i5-8365U has a specified memory bandwidth of 38.4 GB/s, while the i5-1135G7's bandwidth is not listed. Neither processor supports ECC memory. The integrated graphics differ as noted, with Iris Xe Graphics G7 80EU on the newer part versus UHD Graphics 620 on the older one.

FAQ

Q: Which processor is faster in multi-threaded workloads?

A: The Intel Core i5-1135G7 is significantly faster in multi-threaded tests. It scores 7909 in Cinebench R23 multi-core versus 5050 for the i5-8365U, a 56.6% advantage. The PassMark multithread test shows a similar 59.2% lead, with scores of 9512 versus 5976.

Q: How much better is single-core performance on the i5-1135G7?

A: The i5-1135G7 leads by 57.7% in Cinebench R15 single-core (112 versus 71) and by 56.5% in Cinebench R23 single-core (1116 versus 713). In PassMark single-thread, the advantage is 27.4%, with scores of 2640 versus 2073.

Q: What is the most dramatic performance gap between the two?

A: The largest delta is in the PassMark data encryption test, where the i5-1135G7 scores 5465 versus 2006 for the i5-8365U, a 172.4% improvement. This suggests a major upgrade in cryptographic instruction handling.

Q: Are these processors socket-compatible?

A: No, they use different sockets. The i5-1135G7 uses Intel BGA 1449, while the i5-8365U uses Intel BGA 1528. They are not interchangeable in the same motherboard.

Q: Which processor has better integrated graphics?

A: The i5-1135G7 features Iris Xe Graphics G7 with 80 execution units, which is a newer and more capable GPU than the UHD Graphics 620 found in the i5-8365U.

Q: What are the cache size differences?

A: The i5-1135G7 has 80 KB of L1 cache per core, 1.25 MB of L2 per core, and 8 MB of shared L3. The i5-8365U has 64 KB L1 per core, 256 KB L2 per core, and 6 MB of shared L3. The larger caches on the i5-1135G7 contribute to its performance advantages in memory-sensitive workloads.