Intel Core i7-2600K vs Intel Core i7-3820 Comparison

The Intel Core i7-2600K and Intel Core i7-3820 are two end-of-life desktop processors from Intel, both built on the 32 nm Sandy Bridge architecture but targeting different platforms. The data shows a consistent performance advantage for the i7-3820 across all six head-to-head benchmark comparisons, yet the average benchmark scores are remarkably close, with the i7-2600K averaging 1433 and the i7-3820 averaging 1424. This apparent contradiction between individual test wins and overall average suggests a nuanced story where the i7-3820's victories are consistent but narrow, while the i7-2600K's strengths lie in areas not captured by the Cinebench suite. Both processors sit at the 37th percentile of all CPUs, indicating they are closely matched in the broader performance landscape.

Where Each One Wins

The benchmark data is unambiguous regarding specific workloads: the Intel Core i7-3820 wins every single head-to-head comparison listed, from Cinebench R15 through R23, in both multi-core and single-core tests. This makes the i7-3820 the clear choice for rendering workloads, as Cinebench is a standard measure of CPU rendering performance. The i7-3820's lead is consistent, ranging from a 4.3% advantage in Cinebench R15 single-core to a 5.5% lead in both Cinebench R20 and R23 single-core tests. For users whose primary tasks are 3D rendering or other heavily threaded content creation, the data points squarely at the i7-3820.

However, the i7-2600K does not win a single benchmark in the head-to-head comparison, yet its average benchmark score of 1433 is higher than the i7-3820's 1424. This discrepancy is explained by the fact that the i7-2600K has additional benchmark results in the Geekbench suite—scoring 2613 in multi-core and 768 in single-core—which are not included in the head-to-head table. These Geekbench results boost the i7-2600K's average, suggesting that in other types of workloads, such as general system responsiveness and everyday computing tasks, the i7-2600K may be the more capable performer. The data implies a use-case split: the i7-3820 dominates in rendering-specific tasks, while the i7-2600K may hold its own in broader, less specialized applications.

Architecture Differences

Both processors share the Sandy Bridge architecture and the same 32 nm process node, but they diverge significantly in their implementation. The i7-2600K is codenamed Sandy Bridge, while the i7-3820 uses the Sandy Bridge-E variant, which is a different physical design. The i7-3820 features a larger die size at 294 mm² compared to the i7-2600K's 216 mm², and it packs more transistors—1,270 million versus 1,160 million. This extra hardware translates to a larger L3 cache: the i7-3820 offers 10 MB shared, while the i7-2600K has 8 MB shared. Both have identical per-core L1 and L2 caches at 64 KB and 256 KB respectively.

The platform differences are substantial. The i7-2600K uses Intel Socket 1155, while the i7-3820 requires Intel Socket 2011. The i7-3820's platform supports quad-channel memory, doubling the memory bus width and offering a memory bandwidth of 51.2 GB/s versus the i7-2600K's dual-channel 25.6 GB/s. PCIe connectivity also differs, with the i7-3820 providing Gen 2 with 40 lanes (CPU only) compared to the i7-2600K's Gen 2 with 16 lanes. A notable feature difference is integrated graphics: the i7-2600K includes Intel HD 3000, while the i7-3820 has no integrated graphics at all, requiring a discrete GPU. The base clock speeds differ slightly, with the i7-3820 at 3.60 GHz and the i7-2600K at 3.40 GHz, though both boost to 3.80 GHz. The TDP also escalates from 95 W for the i7-2600K to 130 W for the i7-3820, reflecting the larger, more power-hungry design.

Head-to-Head Benchmarks

The Cinebench results show a consistent pattern of the i7-3820 outperforming the i7-2600K by a narrow margin. In Cinebench R15 multi-core, the i7-3820 scores 496 against the i7-2600K's 469, a delta of -5.4% from the i7-2600K's perspective. The single-core test in R15 shows a similar story: 69 versus 66, a -4.3% difference. This pattern continues into R20, where the i7-3820 leads 2067 to 1955 in multi-core (-5.4%) and 291 to 275 in single-core (-5.5%). The R23 results mirror the earlier tests, with the i7-3820 winning multi-core 4923 to 4657 (-5.4%) and single-core 695 to 657 (-5.5%).

The consistency of these deltas—hovering around 5% in nearly every test—is striking. It suggests that the i7-3820's advantage is not workload-dependent but rather a fundamental architectural benefit. The higher base clock of 3.60 GHz versus 3.40 GHz, combined with the larger cache, likely contributes to this steady lead. However, the margins are modest, meaning the i7-2600K is by no means a slouch; it trails by only 5% in the most demanding rendering tasks. The data reveals that for users with an i7-2600K, the performance gap to the i7-3820 is real but hardly transformative, representing a minor upgrade rather than a generational leap.

The Verdict

Based strictly on the benchmark data, the Intel Core i7-3820 is the superior processor for rendering and multi-threaded workloads. It wins all six head-to-head Cinebench comparisons, with leads between 4.3% and 5.5%. If a user's primary concern is maximizing performance in applications like Cinebench, which are representative of 3D rendering, the i7-3820 is the clear pick. Its higher base clock and larger L3 cache provide a measurable, if modest, advantage.

For users who prioritize a broader range of tasks, the i7-2600K presents a compelling counterpoint. Its average benchmark score of 1433 is actually higher than the i7-3820's 1424, thanks to strong Geekbench results, which are absent from the head-to-head comparison. The i7-2600K also offers integrated graphics, a significant convenience for systems without a discrete GPU, and it does so at a lower TDP of 95 W versus 130 W. The data suggests that for general-purpose computing, the i7-2600K may offer comparable or even better performance, while being easier on the power budget. The choice hinges on the workload: rendering specialists should lean toward the i7-3820, while general users might find the i7-2600K's balance of performance and efficiency more suitable.

FAQ

Q: Which processor has a higher average benchmark score?

A: The Intel Core i7-2600K has an average benchmark score of 1433, while the Intel Core i7-3820 scores 1424. This means the i7-2600K edges ahead in the overall average, despite losing all head-to-head Cinebench tests.

Q: How much faster is the i7-3820 in multi-core Cinebench R23?

A: The i7-3820 scores 4923 in Cinebench R23 multi-core, compared to the i7-2600K's 4657. This represents a 5.4% advantage for the i7-3820.

Q: Do both processors support integrated graphics?

A: No. The Intel Core i7-2600K includes Intel HD 3000 integrated graphics, while the Intel Core i7-3820 has no integrated graphics and requires a separate graphics card.

Q: What is the difference in memory bandwidth support?

A: The i7-2600K supports dual-channel memory with a bandwidth of 25.6 GB/s, while the i7-3820 supports quad-channel memory with a bandwidth of 51.2 GB/s, doubling the theoretical memory throughput.

Q: Are both processors unlocked for overclocking?

A: Yes, both the Intel Core i7-2600K and the Intel Core i7-3820 have an unlocked multiplier, as indicated by the multiplierUnlocked field being true for both.

Q: Which processor requires a more power-hungry platform?

A: The Intel Core i7-3820 has a TDP of 130 W, which is higher than the i7-2600K's 95 W. This indicates the i7-3820 platform likely requires more robust cooling and power delivery.

Specification Differences

| Specification | Intel Core i7-2600K | Intel Core i7-3820 |

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

| Base Clock | 3.40 GHz | 3.60 GHz |

| TDP | 95 W | 130 W |

| Socket | Intel Socket 1155 | Intel Socket 2011 |

| Codename | Sandy Bridge | Sandy Bridge-E |

| Process Node | 32 nm | 32 nm |

| Transistors | 1,160 million | 1,270 million |

| Die Size | 216 mm² | 294 mm² |

| L3 Cache | 8 MB (shared) | 10 MB (shared) |

| Memory Bus | Dual-channel | Quad-channel |

| Memory Bandwidth | 25.6 GB/s | 51.2 GB/s |

| PCIe | Gen 2, 16 Lanes (CPU only) | Gen 2, 40 Lanes (CPU only) |

| Integrated Graphics | Intel HD 3000 | None |

| Release Date | 2011-01-08 | 2012-02-12 |

| Launch MSRP | $317 | $305 |

| Part Number | SR00C | SR0LD |