Intel Core i3-1305U vs Intel Core i5-1145G7 Comparison

The Intel Core i5-1145G7 and Intel Core i3-1305U are two mobile processors that, despite their different generations and core configurations, land in nearly the same performance tier. The i5-1145G7, a Tiger Lake-U part from 2020, holds a 0.7% lead over the newer Raptor Lake-U i3-1305U in average benchmark score, with 11279 against 11200. Both CPUs sit at the 66th percentile of all processors, making them direct competitors in the thin-and-light laptop space, though the data reveals that each chip has distinct strengths and weaknesses that go far beyond their aggregate scores.

FAQ

Q: Which processor has the higher average benchmark score?

A: The Intel Core i5-1145G7 leads in average benchmark score with 11279, while the Intel Core i3-1305U scores 11200. The delta between them is just 0.7%, placing them at nearly identical performance levels overall.

Q: How do the core and thread counts differ between the two chips?

A: The i5-1145G7 has 4 cores and 8 threads, while the i3-1305U has 5 cores and 6 threads. The i3-1305U has one more physical core but two fewer threads, indicating a hybrid design without full symmetric multi-threading.

Q: Which CPU wins the most head-to-head benchmark comparisons?

A: The Intel Core i5-1145G7 wins 12 of the 17 head-to-head benchmark tests, while the Intel Core i3-1305U wins 5. The i5-1145G7’s victories are concentrated in multi-threaded and integer workloads, whereas the i3-1305U excels in single-threaded and some math-specific tasks.

Q: What is the difference in integrated graphics between the two?

A: The i5-1145G7 features Iris Xe Graphics G7 with 80 execution units, while the i3-1305U is equipped with UHD Graphics 64EU. The i5-1145G7’s graphics solution has more execution units, which typically translates to better integrated graphics performance.

Q: Are both processors still in production?

A: No. The Intel Core i5-1145G7 is marked as end-of-life, while the Intel Core i3-1305U is listed as active production. The i5-1145G7 was released in September 2020, and the i3-1305U followed in January 2023.

Q: How do their memory support options differ?

A: The i5-1145G7 supports DDR4 and LPDDR4X memory, while the i3-1305U supports DDR4 and DDR5. Both use a dual-channel memory bus, but the i3-1305U adds compatibility with newer DDR5 modules.

Architecture Differences

The two processors represent different Intel architectures and manufacturing generations. The Intel Core i5-1145G7 is built on the Tiger Lake architecture with the codename Tiger Lake-U, and its generation is listed as Core i5 (Willow Cove-U). The Intel Core i3-1305U uses the Raptor Lake architecture with the codename Raptor Lake-U, specifically Core i3 (Raptor Lake-U). Both are fabricated on Intel’s 10 nm process node, though the i5-1145G7 has a die size of 144 mm² while the i3-1305U’s die size is not listed.

Core configuration is another major architectural split. The i5-1145G7 uses 4 cores with 8 threads, typical of a traditional symmetric multi-threading design. The i3-1305U has 5 cores and 6 threads, a configuration that suggests a hybrid arrangement with performance and efficiency cores, though the exact core mix is not specified in the data. This difference directly impacts workload handling: the i5-1145G7 can process more threads simultaneously, while the i3-1305U relies on additional physical cores for scaling.

Cache hierarchies are similar in per-core structure but differ in total shared L3 cache. Both chips have 80 KB of L1 cache per core and 1.25 MB of L2 cache per core. The i5-1145G7 has 8 MB of shared L3 cache, while the i3-1305U has 10 MB of shared L3 cache, giving the newer part a 2 MB advantage in last-level cache.

Memory support also reflects generational progress. The i5-1145G7 supports DDR4 and LPDDR4X, whereas the i3-1305U supports DDR4 and DDR5. The i3-1305U also has more PCIe lanes, with Gen 4 and 8 lanes (CPU only), versus the i5-1145G7’s Gen 4 and 4 lanes (CPU only). Both are mobile segments with no ECC memory support and locked multipliers.

The Verdict

The data paints a clear picture of two chips with different philosophies. The Intel Core i5-1145G7 is the better choice for users who prioritize multi-threaded performance and integer-heavy workloads. Its 12 head-to-head wins, including 8.3% leads across all Cinebench R15, R20, and R23 multi-core tests, make it the stronger all-around processor for tasks that scale with thread count. The i5-1145G7 also dominates in data compression with 103172 points versus 92767 for the i3-1305U, an 11.2% advantage, and in extended instructions where it leads by 38.1% with 7235 against 5240.

The Intel Core i3-1305U, however, wins where single-threaded speed matters most. It posts a 12.9% lead in PassMark single-thread performance, scoring 3115 against 2713 for the i5-1145G7. The i3-1305U also takes wins in data encryption (5895 vs 5406), floating-point math (19687 vs 19233), and prime number finding (36 vs 33). For users running lightly threaded applications or workloads that favor newer instruction-level efficiency, the i3-1305U offers a tangible edge.

The i5-1145G7 is better for general productivity and multi-tasking, given its thread advantage and broader benchmark dominance. The i3-1305U is better for single-threaded responsiveness and tasks like encryption or floating-point calculations. Both are 66th percentile CPUs, so neither is a performance outlier; the choice comes down to workload patterns rather than raw capability. The i5-1145G7’s end-of-life status means it will be harder to source, while the i3-1305U remains active in production. The i5-1145G7 also has the Iris Xe Graphics G7 80EU, which is likely superior to the i3-1305U’s UHD Graphics 64EU for integrated graphics tasks.

Specification Differences

The two processors diverge on nearly every core specification. The i5-1145G7 has 4 cores and 8 threads, while the i3-1305U has 5 cores and 6 threads. Base clock speeds differ dramatically: the i5-1145G7 runs at 2.60 GHz, while the i3-1305U has a base clock of 1600.00 MHz. Boost clocks are closer, with the i5-1145G7 reaching 4.40 GHz and the i3-1305U boosting to 4.50 GHz. Thermal design power also separates them: the i5-1145G7 is rated at 28 W, while the i3-1305U is a more efficient 15 W part.

Sockets are incompatible between the two, with the i5-1145G7 using Intel BGA 1449 and the i3-1305U using Intel BGA 1744. The i5-1145G7’s L3 cache is 8 MB shared, whereas the i3-1305U has 10 MB shared. Memory support differs as noted: the i5-1145G7 supports DDR4 and LPDDR4X, while the i3-1305U supports DDR4 and DDR5. The i3-1305U has double the PCIe lanes at 8, versus 4 for the i5-1145G7, both Gen 4.

Integrated graphics are another clear differentiator. The i5-1145G7 comes with Iris Xe Graphics G7 80EU, while the i3-1305U has UHD Graphics 64EU. The i5-1145G7’s larger execution unit count suggests better graphics performance. Release dates and production status also differ: the i5-1145G7 launched September 2020 and is end-of-life, while the i3-1305U launched January 2023 and is active. Both have a launch MSRP of $309, and neither has an unlocked multiplier.

Head-to-Head Benchmarks

The head-to-head results show a consistent pattern of i5-1145G7 dominance in multi-core and integer tests, with i3-1305U wins in specific single-thread and math workloads. In Cinebench R15 multi-core, the i5-1145G7 scores 783 against 723 for the i3-1305U, an 8.3% win. The same 8.3% margin appears in Cinebench R20 multi-core (3266 vs 3016) and Cinebench R23 multi-core (7777 vs 7183). Single-core Cinebench results follow suit, with the i5-1145G7 leading by 7.8% in R15 (110 vs 102) and 8.5% in R20 (461 vs 425), plus 8.3% in R23 (1098 vs 1014).

PassMark tests reveal deeper specialization. The i5-1145G7 wins integer math by 14.9% (32087 vs 27925) and random string sorting by 16.2% (12658 vs 10889). Its largest victory is in extended instructions, where it scores 7235 against 5240, a 38.1% margin. Data compression also favors the i5-1145G7 at 103172 vs 92767, an 11.2% advantage. The i5-1145G7 wins multithread (9452 vs 8747, 8.1%) and physics (568 vs 523, 8.6%).

The i3-1305U’s wins are fewer but notable. Its biggest is PassMark single-thread, where it scores 3115 against 2713, a 12.9% lead. It also wins data encryption with 5895 vs 5406, an 8.3% margin, and floating-point math at 19687 vs 19233, a 2.3% edge. In find prime numbers, the i3-1305U scores 36 versus 33 for the i5-1145G7, another 8.3% win. The i3-1305U does not win any Cinebench test, while the i5-1145G7 does not win any single-thread PassMark test. This split suggests the i3-1305U’s newer architecture offers better single-core efficiency, but the i5-1145G7’s extra threads and higher TDP provide superior multi-threaded throughput across the board.