Intel Core i3-8109U vs Intel Core i7-3615QM Comparison

The Intel Core i7-3615QM and the Intel Core i3-8109U represent two very different design philosophies from Intel, separated by six years of process and architectural evolution. The data shows a clear split: the i7-3615QM, with its 4 cores and 8 threads, dominates in multi-threaded workloads, while the i3-8109U, with only 2 cores and 4 threads, delivers a decisive victory in single-threaded and Geekbench tests. The i7-3615QM wins 5 of the 8 head-to-head benchmark comparisons, but the i3-8109U’s wins are substantial, often by margins exceeding 50 percent. For users prioritizing raw parallel processing, the older i7 is the clear choice; for those needing snappy single-core responsiveness and modern IPC, the i3-8109U is the better fit.

The Verdict

The benchmark data paints a nuanced picture where the "better" processor depends entirely on the workload. The Intel Core i7-3615QM wins the majority of head-to-head tests, 5 out of 8, with particularly strong showings in Cinebench multi-core and single-core tests. In Cinebench R23 multi-core, the i7-3615QM scores 4393, a full 24% ahead of the i3-8109U’s 3544. Similarly, in Cinebench R20 multi-core, the i7 scores 1845 versus 1488 for the i3, another 24% advantage. These consistent margins in the 24% range across Cinebench R20 and R23 multi-core tests indicate a decisive, repeatable advantage for the i7 in sustained parallel workloads.

However, the Intel Core i3-8109U strikes back decisively in Geekbench and in Cinebench R15 single-core. The i3-8109U scores 1188 in Geekbench single-core, a staggering 53.4% higher than the i7-3615QM’s 554. In Geekbench multi-core, the i3 scores 2454 versus 1907 for the i7, a 22.3% lead. The i3-8109U also wins Cinebench R15 single-core with a score of 138.65, which is 55.3% higher than the i7’s 62. This suggests that for everyday tasks that rely on single-thread performance, the i3-8109U is vastly more responsive, despite having half the cores and threads.

The verdict is straightforward. The i7-3615QM is the processor for rendering, video encoding, and other heavily threaded applications, as evidenced by its 24% lead in Cinebench R23 multi-core. The i3-8109U is the processor for general use, web browsing, and older or poorly optimized software that favors high single-core speed. Given that the i3-8109U is marked as "Active" in production status while the i7-3615QM has no listed production status, the i3-8109U is the more modern and supportable option for new systems. The i7-3615QM, despite its age, remains relevant only for specific multi-threaded use cases.

Where Each One Wins

The i7-3615QM wins all multi-core Cinebench tests and also surprisingly wins the Cinebench R20 and R23 single-core tests. The data shows the i7-3615QM leads in Cinebench R20 single-core with a score of 260 versus 210 for the i3-8109U, a 23.8% margin. In Cinebench R23 single-core, the i7 scores 620 versus 500, another 24% win. This is an important distinction: the i7-3615QM is not merely a multi-core brute; it also outpaces the i3-8109U in newer Cinebench single-core versions, which may reflect different instruction set utilization or memory bandwidth characteristics.

The i3-8109U wins decisively in Geekbench single-core and multi-core, as well as in Cinebench R15 single-core. The Geekbench results are particularly striking: the i3’s 1188 single-core score is more than double the i7’s 554. The multi-core Geekbench score of 2454 for the i3 also beats the i7’s 1907, indicating that in this particular benchmark, the i3’s higher clock speeds and newer architecture compensate for its lack of cores. The i3-8109U also wins Cinebench R15 single-core by a massive 55.3%, suggesting that in older benchmark versions, the i3’s IPC advantage is even more pronounced.

For a user, this means the i7-3615QM is the winner for tasks like video rendering, 3D modeling, and batch processing, where Cinebench scores are predictive of real-world performance. The i3-8109U is the winner for tasks like spreadsheet manipulation, software compilation, and general desktop responsiveness, where Geekbench scores are more indicative. The i7-3615QM’s wins in Cinebench R20 and R23 single-core suggest it can handle modern single-threaded loads better than the i3, but the i3’s massive Geekbench lead implies it excels in a broader range of everyday scenarios.

Architecture Differences

The architectural divide between these two chips is substantial, explaining the benchmark divergence. The Intel Core i7-3615QM is built on the Ivy Bridge architecture using a 22 nm process node, with a die size of 160 mm² and 1,400 million transistors. It is a 4-core, 8-thread processor with a base clock of 2.30 GHz and a boost clock of 3.30 GHz. Its cache hierarchy includes 64 KB of L1 per core, 256 KB of L2 per core, and 6 MB of shared L3 cache. It uses the Intel BGA 1224 socket and has a TDP of 45 watts. Its integrated graphics are Intel HD 4000.

In contrast, the Intel Core i3-8109U is built on the Kaby Lake architecture using a 14 nm process node, with a smaller die size of 123 mm² and no listed transistor count. It is a 2-core, 4-thread processor with a base clock of 3.00 GHz and a boost clock of 3.60 GHz. Its cache includes 64 KB of L1 per core, 256 KB of L2 per core, and 4 MB of shared L3 cache. It uses the Intel BGA 1356 socket and has a TDP of 28 watts, significantly lower than the i7-3615QM. Its integrated graphics are the more capable Iris Pro Plus, and it supports DDR4 memory, whereas the i7-3615QM has no listed memory support type.

The core count and clock speed differences are the primary drivers of performance. The i7-3615QM’s 4 cores and 8 threads give it a raw parallel processing advantage, allowing it to win multi-core Cinebench tests. The i3-8109U’s higher base and boost clocks (3.00/3.60 GHz versus 2.30/3.30 GHz) and newer architecture give it a per-core performance edge, which is why it dominates Geekbench. The i3-8109U’s lower TDP of 28 watts versus 45 watts also makes it more suitable for thinner, lighter laptops, though it sacrifices multi-core capability to achieve this efficiency.

FAQ

Q: Which processor has more cores and threads?

A: The Intel Core i7-3615QM has 4 cores and 8 threads, while the Intel Core i3-8109U has 2 cores and 4 threads. This gives the i7-3615QM a significant advantage in multi-threaded workloads.

Q: Why does the i3-8109U win Geekbench despite having fewer cores?

A: The i3-8109U has a higher base clock (3.00 GHz versus 2.30 GHz) and boost clock (3.60 GHz versus 3.30 GHz) and is built on a newer 14 nm Kaby Lake architecture. In Geekbench, the i3-8109U scores 2454 multi-core and 1188 single-core, compared to the i7-3615QM’s 1907 and 554, due to its superior per-core IPC.

Q: Which processor is better for Cinebench R23 multi-core rendering?

A: The Intel Core i7-3615QM is clearly better, scoring 4393 in Cinebench R23 multi-core, which is 24% higher than the i3-8109U’s 3544. The i7’s 4 cores and 8 threads are better suited for this type of parallel workload.

Q: What are the TDP differences between the two?

A: The i7-3615QM has a TDP of 45 watts, while the i3-8109U has a TDP of 28 watts. The i3-8109U is more power-efficient, making it more suitable for thinner laptops, but the i7-3615QM offers more raw multi-core performance at the cost of higher power consumption.

Q: Which processor has a larger L3 cache?

A: The i7-3615QM has 6 MB of shared L3 cache, while the i3-8109U has 4 MB of shared L3 cache. The i7-3615QM also has a larger die size at 160 mm² versus 123 mm² for the i3-8109U.

Q: In how many head-to-head benchmarks does each processor win?

A: The i7-3615QM wins 5 of the 8 head-to-head benchmarks, including all multi-core Cinebench tests and Cinebench R20 and R23 single-core tests. The i3-8109U wins 3 of the 8, including all Geekbench tests and Cinebench R15 single-core.

Head-to-Head Benchmarks

The benchmark results reveal a consistent pattern where the i7-3615QM wins on Cinebench multi-core and newer single-core versions, while the i3-8109U dominates older single-core and Geekbench tests. Starting with Cinebench R15, the i7-3615QM scores 442 in multi-core, a 23.8% lead over the i3-8109U’s 357. However, in R15 single-core, the tables turn dramatically: the i3-8109U scores 138.65, which is 55.3% higher than the i7-3615QM’s 62. This is the largest single-core margin in the entire dataset.

Moving to Cinebench R20, the i7-3615QM wins both tests. In multi-core, it scores 1845 versus 1488, a 24% advantage. In single-core, it scores 260 versus 210, another 23.8% win. This is a notable reversal from R15, indicating that the i7-3615QM’s architecture handles the newer R20 workload’s single-threaded portion better than the i3-8109U. The pattern continues in Cinebench R23, where the i7-3615QM wins multi-core with 4393 versus 3544 (24% lead) and single-core with 620 versus 500 (24% lead).

The Geekbench results are where the i3-8109U shines. In Geekbench single-core, the i3-8109U scores 1188, a 53.4% lead over the i7-3615QM’s 554. In Geekbench multi-core, the i3-8109U scores 2454, a 22.3% lead over the i7-3615QM’s 1907. These results suggest that the i3-8109U’s higher clocks and newer architecture are more beneficial in Geekbench’s workload, which may rely more on memory latency and branch prediction than on raw core count.

The biggest win for the i7-3615QM is its consistent 24% lead across Cinebench R20 and R23 multi-core tests, indicating that its 4-core, 8-thread configuration is optimally utilized in rendering workloads. The biggest win for the i3-8109U is its 55.3% lead in Cinebench R15 single-core, which highlights the massive IPC improvement Intel achieved between Ivy Bridge and Kaby Lake. Overall, the i7-3615QM is the multi-core champion, while the i3-8109U is the single-core and Geekbench champion, making the choice between them a trade-off between parallel throughput and per-core speed.