Intel Core i3-3240 vs Intel Core i7-3687U Comparison

Head-to-Head Benchmarks

The benchmark data presents a clear split between these two Ivy Bridge processors. The Intel Core i7-3687U wins five of the seven recorded head-to-head tests, while the Intel Core i3-3240 takes the remaining two. The margins, however, tell a more nuanced story than the raw win count.

In the Cinebench suite, the i7-3687U is consistently ahead. In Cinebench R15 multicore, it scores 224 against 201 for the i3-3240, a lead of 11.4 percent. Moving to Cinebench R20 multicore, the i7-3687U posts 937 versus 840, an 11.5 percent advantage. The Cinebench R23 multicore test shows 2231 against 2000, a margin of 11.6 percent. Single-core results follow the same pattern: Cinebench R20 single-core gives the i7-3687U a 132 to 118 win (11.9 percent), and Cinebench R23 single-core shows 315 versus 282 (11.7 percent). These are consistent, near-uniform advantages across the entire Cinebench lineup.

The Geekbench tests flip the outcome decisively. In Geekbench multicore, the i3-3240 scores 1233 against 1044 for the i7-3687U, a 15.3 percent advantage. Geekbench single-core shows 650 versus 526, a 19.1 percent lead for the desktop chip. These are larger margins than any of the Cinebench deltas, suggesting the Geekbench workload favors the i3-3240's higher base clock and desktop-oriented design.

The average benchmark scores reflect this mixed picture. The i7-3687U averages 773 across all tests, placing it at the 21st percentile of all CPUs in the database. The i3-3240 averages 761, at the 20th percentile. The 12-point gap in average scores is modest, and the percentile difference is just one point. The nearest rivals for the i7-3687U include the Intel Core i5-680 (average 772, delta 0.2 percent) and the Intel Core i3-3250T (average 775, delta -0.2 percent). For the i3-3240, the closest competitors include the AMD A8-6600K (average 764, delta -0.3 percent) and the Intel Core i5-3210M (average 758, delta 0.4 percent). Both processors sit in a tightly packed performance band where a few points separate them from their nearest neighbors.

Architecture Differences

Both processors share the same fundamental architecture: Ivy Bridge, built on Intel's 22 nm process. Both have 2 physical cores with 4 threads, meaning hyper-threading is active on each. Both support DDR3 memory over a dual-channel bus, and neither supports ECC memory. Both have locked multipliers, so neither can be overclocked by changing the multiplier.

The differences emerge in several key areas. The i7-3687U has a base clock of 2.10 GHz and a boost clock of 3.30 GHz, allowing it to scale up under load. The i3-3240 has a base clock of 3.40 GHz and no boost clock at all, so it runs at a fixed frequency. This explains the Geekbench results: the i3-3240's higher sustained clock gives it an edge in workloads that do not benefit from the i7's turbo behavior.

Cache allocation also differs. The i7-3687U carries 4 MB of shared L3 cache, while the i3-3240 has 3 MB. Both have 64 KB of L1 cache per core and 256 KB of L2 cache per core, so the L3 difference is the only cache disparity. The die size reflects this: the i7-3687U measures 118 mm², while the i3-3240 is smaller at 94 mm².

Power and packaging are starkly different. The i7-3687U has a TDP of 17 watts and uses the Intel BGA 1023 socket, marking it as a mobile part. The i3-3240 has a TDP of 55 watts and uses the Intel Socket 1155, a desktop platform. The 38-watt TDP gap is substantial and directly influences where each processor can be deployed.

Integrated graphics differ as well. The i7-3687U includes Intel HD 4000, while the i3-3240 has Intel HD 2500. The PCIe configuration is only listed for the i3-3240: Gen 3 with 16 lanes (CPU only). The i7-3687U has no PCIe data recorded in the database.

Release dates place the i3-3240 first, arriving on September 2, 2012, while the i7-3687U followed on January 7, 2013. Part numbers are SR0RH for the i3-3240 and SR0XH for the i7-3687U. Neither has a recorded launch MSRP, and no production status is listed for either.

Where Each One Wins

The i7-3687U wins across every Cinebench test in the database, both single-core and multicore. The margins are tight, between 11.4 and 11.9 percent, but they are uniform. This suggests the i7-3687U handles the Cinebench rendering workloads more efficiently, likely due to its larger L3 cache and boost clock behavior. Users running Cinebench-style rendering tasks would see a consistent, if modest, advantage from the mobile chip.

The i3-3240 wins both Geekbench tests, with a 15.3 percent lead in multicore and a 19.1 percent lead in single-core. The Geekbench suite appears to reward the i3-3240's higher base clock of 3.40 GHz, which never drops or throttles in the way a boost clock might on a mobile part. The fixed 3.40 GHz clock is simply higher than the i7-3687U's 2.10 GHz base, and in Geekbench's mixed workload, that sustained frequency wins out.

The overall win count favors the i7-3687U at 5 wins versus 2 for the i3-3240. However, the magnitude of the Geekbench losses for the i7-3687U (15.3 and 19.1 percent) is larger than any of its own Cinebench wins. This means a user's choice depends heavily on which benchmark suite reflects their actual workload.

FAQ

Q: Which processor has the higher average benchmark score?

A: The Intel Core i7-3687U has an average benchmark score of 773, compared to 761 for the Intel Core i3-3240. The 12-point gap places the i7-3687U at the 21st percentile and the i3-3240 at the 20th percentile of all CPUs.

Q: Why does the i3-3240 win the Geekbench tests despite losing the Cinebench tests?

A: The i3-3240 has a base clock of 3.40 GHz with no boost clock, while the i7-3687U has a 2.10 GHz base and a 3.30 GHz boost. The Geekbench workload appears to favor the i3-3240's sustained higher frequency, resulting in a 15.3 percent multicore win and a 19.1 percent single-core win.

Q: What are the TDP differences between these two processors?

A: The i7-3687U has a TDP of 17 watts, while the i3-3240 has a TDP of 55 watts. This 38-watt difference reflects the mobile design of the i7-3687U versus the desktop design of the i3-3240.

Q: Do both processors have the same number of cores and threads?

A: Yes, both have 2 cores and 4 threads. They also share the same Ivy Bridge architecture and 22 nm process node.

Q: Which processor has more L3 cache?

A: The i7-3687U has 4 MB of shared L3 cache, while the i3-3240 has 3 MB. Both have 64 KB of L1 per core and 256 KB of L2 per core.

Q: What integrated graphics do these processors include?

A: The i7-3687U includes Intel HD 4000, while the i3-3240 includes Intel HD 2500.

Specification Differences

| Specification | Intel Core i7-3687U | Intel Core i3-3240 |

|---|---|---|

| Base clock | 2.10 GHz | 3.40 GHz |

| Boost clock | 3.30 GHz | None |

| TDP | 17 W | 55 W |

| Socket | Intel BGA 1023 | Intel Socket 1155 |

| Die size | 118 mm² | 94 mm² |

| L3 cache | 4 MB (shared) | 3 MB (shared) |

| Integrated graphics | Intel HD 4000 | Intel HD 2500 |

| PCIe | Not listed | Gen 3, 16 Lanes (CPU only) |

| Market segment | Mobile | Desktop |

| Release date | 2013-01-07 | 2012-09-02 |

| Part number | SR0XH | SR0RH |

The two processors share their architecture (Ivy Bridge), process node (22 nm), foundry (Intel), core count (2), thread count (4), memory support (DDR3), memory bus (Dual-channel), ECC support (false), and multiplier unlock status (false).

The Verdict

The data points to a workload-dependent decision. The Intel Core i7-3687U is the stronger choice for Cinebench-style rendering tasks, where it wins every test with margins between 11.4 and 11.9 percent. Its larger L3 cache, boost clock, and lower TDP make it suitable for mobile systems where power efficiency matters. The i7-3687U also holds a slight edge in average benchmark score (773 versus 761) and percentile ranking (21st versus 20th).

The Intel Core i3-3240 is the pick for Geekbench-style workloads, where it leads by 15.3 percent in multicore and 19.1 percent in single-core. Its fixed 3.40 GHz clock provides consistent performance without boost variability. The desktop socket, higher TDP, and PCIe Gen 3 support make it a straightforward fit for desktop builds, though its smaller L3 cache and older integrated graphics are drawbacks.

Users prioritizing Cinebench rendering performance and mobile deployment should choose the i7-3687U. Users prioritizing Geekbench scores and desktop compatibility should choose the i3-3240. The overall win count (5 to 2) favors the i7-3687U, but the larger Geekbench losses mean no universal winner exists. Each processor dominates in its preferred benchmark family, and the choice should follow the user's actual application mix.