Intel Core i7-860 vs Intel Core i7-940 Comparison

Head-to-Head Benchmarks

The benchmark data is unambiguous: the Intel Core i7-940 wins every recorded head-to-head test against the Intel Core i7-860. Across five Cinebench workloads, the i7-940 takes all five, with the i7-860 finishing without a single victory. The margins are narrow, ranging from 1.9% to 2.0%, but they are consistent in every category.

In Cinebench R15 multicore, the i7-940 scores 264 versus the i7-860's 259, a 1.9% lead. The same 1.9% delta appears in Cinebench R20 multicore, where the i7-940 posts 1102 against 1081. Single-core results follow the same pattern: in Cinebench R20 single-core, the i7-940 scores 155 and the i7-860 scores 152, a 2.0% advantage. Cinebench R23 repeats this, with the i7-940 at 370 and the i7-860 at 363 in single-core, a 1.9% gap, and 2626 versus 2574 in multicore, another 2.0% edge.

These are not dramatic differences, but they are uniform. No workload flips the result. The i7-940's advantage holds whether the test stresses all cores or just one. The recorded data shows the i7-940 as the faster processor across the board, though the i7-860 remains close enough that the gap is unlikely to be felt in most real-world tasks. For a buyer prioritizing maximum benchmark output, the i7-940 is the clear pick from these numbers.

Architecture Differences

Both processors belong to Intel's Nehalem architecture and are built on the same 45 nm process node, but they diverge in platform and internal design. The i7-940 uses the Bloomfield codename and targets Intel Socket 1366, while the i7-860 uses Lynnfield and fits Intel Socket 1156. The i7-940 is part of the Core i7 (Bloomfield) generation, and the i7-860 is Core i7 (Lynnfield). Both are desktop parts, and both are end-of-life products.

Core and thread counts are identical: 4 cores and 8 threads each. Cache layouts match as well, with 64 KB of L1 per core, 256 KB of L2 per core, and 8 MB of shared L3. The transistor counts differ slightly: the i7-940 packs 731 million transistors on a 263 mm² die, while the i7-860 has 774 million transistors on a 296 mm² die. The larger die and higher transistor count for the i7-860 reflect its integrated memory controller and other platform differences, though the cache structure remains the same.

Clock speeds tell a different story. The i7-940 has a base clock of 2.93 GHz and a boost clock of 3.20 GHz. The i7-860 starts lower at 2.80 GHz base but boosts higher to 3.47 GHz. Despite the i7-860's higher boost, the i7-940 still wins every benchmark, suggesting the i7-940's base frequency and other architectural factors compensate for the lower boost ceiling.

The memory bus is a major differentiator. The i7-940 uses triple-channel DDR3 memory, while the i7-860 uses dual-channel DDR3. This means the i7-940 can access more memory bandwidth in theory, which may contribute to its multicore wins. Both support DDR3 memory, and neither supports ECC memory. PCIe support is Gen 2 for both, but the i7-860 specifies 16 lanes (CPU only), while the i7-940 lists only "Gen 2" without a lane count in the recorded data.

Power consumption is another split: the i7-940 has a TDP of 130 watts, while the i7-860 draws only 95 watts. The i7-860 is significantly more power-efficient, which is a meaningful advantage for system builders concerned about heat or electricity usage. The i7-940's higher TDP aligns with its higher base clock and triple-channel memory controller.

The i7-940 was released on November 16, 2008, while the i7-860 arrived on September 7, 2009, nearly a year later. The i7-860's part number is SLBJJ, and the i7-940's is SLBCK. Neither processor has an unlocked multiplier, so overclocking is limited to base clock adjustments. Neither has integrated graphics, so a discrete GPU is mandatory for both.

Where Each One Wins

The i7-940 wins every benchmark in the database, so the performance split is one-sided. However, the context matters. The i7-940's wins are consistent but small, and the i7-860 offers a different set of trade-offs that might appeal to specific use cases.

For raw compute performance, the i7-940 is the winner. Cinebench R15, R20, and R23 multicore tests all favor it, with deltas of 1.9% to 2.0%. Single-core tests also go to the i7-940, with the same margins. If the workload is purely about squeezing the most points out of Cinebench, the i7-940 is the answer.

The i7-860 wins in efficiency. Its TDP of 95 watts is 35 watts lower than the i7-940's 130 watts. For a compact desktop build, a lower-power system, or a user sensitive to heat output, the i7-860 is the better choice despite the small performance deficit. The i7-860 also boosts to 3.47 GHz, which is higher than the i7-940's 3.20 GHz, but that advantage does not translate into benchmark victories in the recorded data.

The i7-860 uses dual-channel memory, which is simpler and often cheaper to populate than the i7-940's triple-channel setup. For a mainstream user who does not need the extra memory bandwidth, the i7-860's platform may be more practical. The i7-940's triple-channel support offers a theoretical bandwidth edge, but the benchmark gap does not reflect a large real-world difference.

The i7-940 has a higher base clock at 2.93 GHz versus 2.80 GHz, which gives it a steady-state advantage in sustained loads. The i7-860's higher boost clock of 3.47 GHz is a peak figure that it reaches under light load, but the i7-940's superior base frequency appears to be more impactful in the Cinebench tests.

The Verdict

The data points to the Intel Core i7-940 as the faster processor. It wins all five head-to-head benchmark comparisons, with a 1.9% to 2.0% lead in every test. Its average benchmark score is 903, compared to the i7-860's 886, and both sit at the 24th percentile among all CPUs. The i7-940's nearest rivals include the Intel Core i5-5350U at the same average score and the AMD A10-7860K slightly ahead, while the i7-860's rivals include the AMD PRO A8-8650B and the Intel Pentium G4560T.

For a user who prioritizes maximum Cinebench scores, the i7-940 is the choice. The margins are slim, but they are consistent across multicore and single-core workloads. The i7-940's triple-channel memory bus and higher base clock likely contribute to its edge.

However, the i7-860 is not without merit. Its 95-watt TDP is substantially lower than the i7-940's 130 watts, making it a more energy-conscious option. It also has a higher boost clock at 3.47 GHz, though that does not show up as a win in the benchmarks. The i7-860's dual-channel memory may be easier to configure in a mainstream build.

Strictly from the data, the i7-940 is the winner for performance. The i7-860 is the winner for efficiency and platform simplicity. Users who want the fastest recorded scores should pick the i7-940. Users who value lower power draw and are willing to sacrifice roughly 2% performance should consider the i7-860.

FAQ

Q: Which processor has a higher average benchmark score?

A: The Intel Core i7-940 has an average benchmark score of 903, while the Intel Core i7-860 scores 886.

Q: How much faster is the i7-940 in Cinebench R23 multicore?

A: The i7-940 scores 2626 versus the i7-860's 2574, a 2.0% lead.

Q: What is the TDP difference between the two?

A: The i7-940 has a TDP of 130 watts, and the i7-860 has a TDP of 95 watts.

Q: Do both processors support ECC memory?

A: No, neither the i7-940 nor the i7-860 supports ECC memory.

Q: Which socket does each processor use?

A: The i7-940 uses Intel Socket 1366, and the i7-860 uses Intel Socket 1156.

Q: What is the boost clock of each processor?

A: The i7-940 boosts to 3.20 GHz, while the i7-860 boosts to 3.47 GHz.

Specification Differences

| Specification | Intel Core i7-940 | Intel Core i7-860 |

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

| Base Clock | 2.93 GHz | 2.80 GHz |

| Boost Clock | 3.20 GHz | 3.47 GHz |

| TDP | 130 W | 95 W |

| Socket | Intel Socket 1366 | Intel Socket 1156 |

| Codename | Bloomfield | Lynnfield |

| Generation | Core i7 (Bloomfield) | Core i7 (Lynnfield) |

| Transistors | 731 million | 774 million |

| Die Size | 263 mm² | 296 mm² |

| Memory Bus | Triple-channel | Dual-channel |

| PCIe | Gen 2 | Gen 2, 16 Lanes (CPU only) |

| Release Date | 2008-11-16 | 2009-09-07 |

| Part Number | SLBCK | SLBJJ |