Intel Core i3-5020U vs Intel Core i7-3687U Comparison

The Intel Core i7-3687U and Intel Core i3-5020U are both dual-core mobile processors with four threads, but the benchmark data reveals a clear split in their strengths. The i7-3687U dominates the Cinebench suite, winning all four multicore and singlecore tests with deltas between 18.9% and 20%. However, the i3-5020U delivers a decisive victory in Geekbench, outperforming the i7 by 24.3% in multicore and 24.4% in singlecore. This makes the choice dependent on the workload: the i7-3687U is the stronger option for rendering and sustained compute tasks, while the i3-5020U shows superior performance in Geekbench's mixed workload scenarios.

Where Each One Wins

The Intel Core i7-3687U wins in five of the seven recorded head-to-head benchmarks. Its largest margins come in Cinebench R20 singlecore, where it leads by 20%, and Cinebench R23 singlecore, with a 19.3% advantage. The multicore results follow a similar pattern: Cinebench R15 and R20 both show a 19.1% lead, while Cinebench R23 multicore shows an 18.9% delta. This consistency across the Cinebench family indicates that the i7-3687U benefits from its higher clock ceiling, as its boost clock reaches 3.30 GHz while the i3-5020U has no boost capability and runs at a fixed 2.20 GHz.

The Intel Core i3-5020U wins only two benchmarks, but they are significant. Geekbench multicore shows the i3 at 1379 points versus the i7's 1044 points, a 24.3% gap. Geekbench singlecore follows with 696 points versus 526 points, a 24.4% gap. These results suggest the i3-5020U's architecture, based on Broadwell, handles Geekbench's specific instruction mix more efficiently, despite having a lower base clock. The i7-3687U's older Ivy Bridge design appears to lose ground when the workload does not scale with raw clock speed.

In terms of overall standing, the i7-3687U holds a 21st percentile ranking across all CPUs, while the i3-5020U sits at the 20th percentile. The average benchmark score tells a similar story: 773 points for the i7-3687U and 757 points for the i3-5020U. The i7-3687U's nearest rival, the Intel Core i5-680, scores 772 points, a delta of 0.2%, while the i3-5020U's closest competitor, the Intel Core i5-3210M, scores 758 points, a delta of -0.1%. These aggregate metrics place both processors in the same performance tier, with the i7-3687U holding a marginal edge in overall average.

Architecture Differences

The core counts are identical: both processors feature 2 cores and 4 threads, and both have 64 KB of L1 cache per core and 256 KB of L2 cache per core. The differences emerge in the L3 cache, where the i7-3687U offers 4 MB shared, while the i3-5020U provides 3 MB shared. The i7 also has a larger die size at 118 mm², compared to the i3's 82 mm², and it is built on Intel's 22 nm process node, while the i3 uses the newer 14 nm node.

The i3-5020U is built on the Broadwell architecture, specifically Broadwell-U, which is a newer design than the Ivy Bridge architecture used in the i7-3687U. This architectural gap explains the Geekbench results: Broadwell's improved instruction handling and memory subsystem allow the i3 to outperform the i7 despite a lower base clock and no boost clock. The i3-5020U also lists 1,300 million transistors, while the i7-3687U does not have a recorded transistor count in the database.

Memory support differs in bandwidth: the i3-5020U has a recorded memory bandwidth of 25.6 GB/s, while the i7-3687U has no bandwidth figure. Both use DDR3 memory in dual-channel mode, and neither supports ECC memory. The i3 also lists PCIe Gen 2 with 12 lanes (CPU only), while the i7 has no PCIe data recorded. Integrated graphics differ as well: the i7-3687U uses Intel HD 4000, while the i3-5020U uses Intel HD 5500, a newer generation that may offer better media and display capabilities.

Socket and packaging also separate the two. The i7-3687U uses Intel BGA 1023, while the i3-5020U uses Intel BGA 1168. The i3 has a production status of "End-of-life," while the i7 has no recorded status. Release dates differ by about two years, with the i7-3687U appearing in January 2013 and the i3-5020U in February 2015. The i7's part number is SR0XH, while the i3's is SR240.

Head-to-Head Benchmarks

The Cinebench R15 multicore test gives the i7-3687U a score of 224 points against the i3-5020U's 188 points, a 19.1% lead. This is the smallest multicore delta among the four Cinebench tests, but it still represents a clear victory. In Cinebench R20 multicore, the scores are 937 versus 787, again a 19.1% gap. Cinebench R23 multicore shows 2231 versus 1876, an 18.9% delta. The singlecore results are even more lopsided: Cinebench R20 singlecore shows 132 versus 110, a 20% lead, and Cinebench R23 singlecore shows 315 versus 264, a 19.3% lead.

The Geekbench results flip the narrative. Geekbench multicore gives the i3-5020U a score of 1379 against the i7-3687U's 1044, a 24.3% advantage. Geekbench singlecore shows 696 versus 526, a 24.4% lead for the i3. The magnitude of these deltas is striking: the i3's Geekbench wins are larger than any of the i7's Cinebench wins. This suggests that the i3-5020U is not merely competitive in Geekbench, it is substantially faster, likely due to the Broadwell architecture's more efficient execution of the test's integer and floating-point operations.

The i7-3687U's Cinebench dominance is likely tied to its boost clock of 3.30 GHz, which provides a significant advantage in rendering workloads that scale with frequency. The i3-5020U, locked at 2.20 GHz with no boost, cannot match this. However, the i3's newer 14 nm process and Broadwell design allow it to extract more performance per clock in Geekbench, which is more sensitive to instruction-level efficiency than raw clock speed.

Specification Differences

The core and thread counts are the same, but the clock speeds differ. The i7-3687U has a base clock of 2.10 GHz and a boost clock of 3.30 GHz, while the i3-5020U has a base clock of 2.20 GHz and no boost clock. The TDP values are close: 17 watts for the i7 and 15 watts for the i3. The i7 uses Intel BGA 1023, while the i3 uses Intel BGA 1168. The L3 cache is 4 MB for the i7 and 3 MB for the i3. The process node is 22 nm for the i7 and 14 nm for the i3, with the i3's die size at 82 mm² and the i7's at 118 mm².

The i3-5020U has a recorded memory bandwidth of 25.6 GB/s, while the i7 does not list a bandwidth figure. The i3 also lists PCIe Gen 2 with 12 lanes (CPU only), while the i7 has no PCIe data. Integrated graphics differ, with the i7 using HD 4000 and the i3 using HD 5500. The release dates are over two years apart, with the i7 launching in 2013 and the i3 in 2015. The i3-5020U has an end-of-life production status, and its launch MSRP is $281. The i7-3687U has no recorded launch MSRP.

FAQ

Q: Which processor has a higher boost clock?

A: The Intel Core i7-3687U has a boost clock of 3.30 GHz, while the Intel Core i3-5020U has no boost clock and runs at a fixed 2.20 GHz base clock.

Q: Why does the i3-5020U win in Geekbench despite lower clock speeds?

A: The i3-5020U uses the newer Broadwell architecture on a 14 nm process, compared to the i7-3687U's Ivy Bridge on 22 nm. The database shows Geekbench multicore at 1379 versus 1044 and singlecore at 696 versus 526, indicating the Broadwell design is more efficient in that workload.

Q: What is the L3 cache difference between the two?

A: The i7-3687U has 4 MB of shared L3 cache, while the i3-5020U has 3 MB of shared L3 cache.

Q: Are both processors dual-core with four threads?

A: Yes, both the Intel Core i7-3687U and Intel Core i3-5020U have 2 cores and 4 threads.

Q: Which processor has a smaller die size?

A: The i3-5020U has a die size of 82 mm², while the i7-3687U has a die size of 118 mm².

Q: What is the average benchmark score for each?

A: The i7-3687U has an average benchmark score of 773, while the i3-5020U has an average score of 757. The i7 sits at the 21st percentile, and the i3 at the 20th percentile.

The Verdict

The data points to a clear split. The Intel Core i7-3687U is the processor to choose for Cinebench-style workloads, which emphasize sustained multicore rendering and singlecore frequency. It wins all four Cinebench tests with deltas between 18.9% and 20%, and its boost clock of 3.30 GHz is the primary driver. For users running rendering, video encoding, or any task that scales with clock speed, the i7-3687U is the better pick.

The Intel Core i3-5020U is the better choice for Geekbench-heavy usage, where it leads by 24.3% in multicore and 24.4% in singlecore. Its Broadwell architecture and 14 nm process deliver superior efficiency in that benchmark's instruction mix. The i3 also has a lower TDP of 15 watts versus the i7's 17 watts, making it a slightly more power-efficient option in a thin-and-light laptop.

The overall average benchmark scores are close, with the i7 at 773 and the i3 at 757, a difference of about 2%. The percentile rankings are similarly tight, at 21 and 20. Neither processor is a dominant overall winner, so the decision comes down to workload. The i7-3687U wins the majority of tests (5 out of 7), but the i3-5020U wins the two Geekbench tests by a larger margin. For rendering, pick the i7-3687U. For mixed general-purpose tasks that resemble Geekbench, the i3-5020U offers better measured performance.