CPU Comparison

# Intel Core i3-7320 vs Intel Core i5-2400

The Intel Core i3-7320 and Intel Core i5-2400 represent two distinct eras of desktop computing, separated by six years of architectural evolution. The i3-7320, built on Kaby Lake with a 14 nm process, stands as an active production part, while the i5-2400, a Sandy Bridge design on 32 nm, is end-of-life. Despite the i5-2400 offering more physical cores (4 vs 2), the benchmark data consistently favors the newer i3-7320 across every head-to-head comparison, with the i3 winning all 5 recorded tests. The average benchmark scores are remarkably close, 1173 for the i3-7320 versus 1187 for the i5-2400, but this masks a decisive performance gap in multi-threaded and single-threaded workloads alike.

Head-to-Head Benchmarks

The most striking result is the consistency of the i3-7320's victories. In Cinebench R15 multicore, the i3-7320 scores 408 against the i5-2400's 329, a 24% advantage. This is notable because the i5-2400 has twice the physical core count (4 vs 2), yet the i3's higher IPC and clock speed overcome that deficit. The single-core Cinebench R15 test shows an even more lopsided result: 57 for the i3-7320 versus 329 for the i5-2400 in multicore, but the single-core score of 57 is anomalously low compared to other tests, likely a data artifact, yet the i3 still wins.

Moving to Cinebench R20, the pattern holds. The i3-7320 posts 1703 in multicore, beating the i5-2400's 1374 by 23.9%. Single-core R20 scores are 240 versus 194, a 23.7% edge. The R23 results mirror this: multicore 4057 for the i3 versus 3272 for the i5 (24% delta), and single-core 572 versus 462 (23.8%). These deltas are remarkably uniform, hovering around 24% across all tests. The i5-2400 does have a Geekbench multicore score of 2011 and a single-core score of 666, but since no corresponding Geekbench data exists for the i3-7320, this comparison is incomplete.

The i3-7320's nearest rivals in overall average score include the Intel Core i7-3635QM (1170, +0.3% delta) and the Core i5-3570S (1169, +0.4% delta), placing it in a competitive mid-range bracket. The i5-2400, meanwhile, sits near the Core i5-4460T (1190, -0.2% delta) and the AMD Opteron 6234 (1191, -0.3% delta). Both CPUs occupy the 33rd percentile of all CPUs, meaning they outperform roughly a third of the database, but the i3-7320 does so with far fewer cores.

Where Each One Wins

The i3-7320 wins every benchmark category, so the question is not where it wins but by how much. Its largest margins come in multi-core workloads, 24% in both R15 and R23, where the i5-2400's physical core advantage is neutralized by architectural shortcomings. The i3-7320's single-core wins (23.7-23.8%) are equally decisive, reflecting the massive IPC improvements between Sandy Bridge and Kaby Lake. For workloads that scale with clock speed and modern instruction sets, such as older games, web browsing, and office applications, the i3-7320 is clearly superior.

The i5-2400's only theoretical advantage lies in its four physical cores versus the i3's two. In applications that are heavily multi-threaded and can use more than four threads, the i5-2400 might have an edge, but the benchmark data does not support this. The i5-2400's best showing is in Geekbench multicore (2011), but without a comparable i3-7320 result, this cannot be validated. The i5-2400 also has a larger L3 cache (6 MB vs 4 MB), which could help in some data-heavy workloads, but again, the benchmarks show no such benefit.

For users with legacy DDR3 memory, the i5-2400 might be the only choice if the motherboard requires that memory type. However, in pure performance terms, the data shows no scenario where the i5-2400 wins. The i3-7320's higher base clock (4.10 GHz vs 3.10 GHz) and boost clock (none for the i3, 3.40 GHz for the i5) ensure it leads in every measured category.

Architecture Differences

The two CPUs are separated by multiple architectural generations. The i3-7320 uses Kaby Lake, built on a 14 nm process, while the i5-2400 uses Sandy Bridge on a 32 nm node. This process shrink allows the i3 to achieve higher clock speeds at lower power, the i3's TDP is 51 watts versus the i5's 95 watts. The i3-7320 has 2 cores and 4 threads (Hyper-Threading enabled), whereas the i5-2400 has 4 cores and 4 threads (no Hyper-Threading). This means the i3 can process 4 threads simultaneously, matching the i5's thread count despite having half the physical cores.

The i3-7320's L3 cache is 4 MB shared, while the i5-2400 has 6 MB shared. Both have identical L1 (64 KB per core) and L2 (256 KB per core) caches. The i3 supports DDR4 memory with a dual-channel bus and 38.4 GB/s bandwidth, while the i5 supports DDR3 with dual-channel but no listed bandwidth figure. This memory difference is significant: DDR4 offers higher bandwidth and lower latency, contributing to the i3's performance lead.

Integrated graphics differ as well: the i3-7320 has Intel HD 630, while the i5-2400 has Intel HD 2000. The i3's newer iGPU supports more modern video decoding and output standards. Both use the same PCIe Gen 3 with 16 lanes (CPU only). The i3-7320's part number is SR358, and the i5's is SR00Q. Neither CPU has an unlocked multiplier, so overclocking is not an option.

The i3-7320 was released on January 2, 2017, while the i5-2400 came out on January 8, 2011. The i5-2400's transistor count is listed at 1,160 million with a die size of 216 mm², while the i3-7320's transistor count and die size are not provided. The i5-2400 is end-of-life, whereas the i3-7320 remains active in production.

FAQ

Q: Does the Intel Core i5-2400's four physical cores give it an advantage in multi-threaded workloads?

A: No. The benchmark data shows the i3-7320 winning all multi-core tests by 23.9-24%. Despite having half the physical cores, the i3's Hyper-Threading and higher clock speed (4.10 GHz vs 3.10 GHz) allow it to outperform the i5's four native cores.

Q: Which CPU has better single-core performance?

A: The i3-7320 wins all single-core benchmarks by 23.7-23.8%. In Cinebench R20 single-core, it scores 240 versus the i5-2400's 194. This reflects the significant IPC improvements between Sandy Bridge (2011) and Kaby Lake (2017).

Q: Are these CPUs comparable in overall average performance?

A: Yes, their average benchmark scores are nearly identical: 1173 for the i3-7320 and 1187 for the i5-2400. Both rank at the 33rd percentile of all CPUs. However, the i3 achieves this with only 2 cores and 4 threads, while the i5 uses 4 cores and 4 threads.

Q: Which CPU is more power-efficient?

A: The i3-7320 has a TDP of 51 watts, compared to 95 watts for the i5-2400. This is a significant difference, especially considering the i3 delivers higher performance across all benchmarks.

Q: Can the i5-2400's larger L3 cache (6 MB vs 4 MB) compensate for its architectural disadvantages?

A: The data does not support this. Despite having 50% more L3 cache, the i5-2400 loses every benchmark by roughly 24%. The i3's newer architecture and faster memory support (DDR4 vs DDR3) more than compensate for the cache deficit.

Q: What are the memory support differences?

A: The i3-7320 supports DDR4 with a dual-channel bus and 38.4 GB/s bandwidth. The i5-2400 supports DDR3 with a dual-channel bus but has no listed bandwidth figure. This means the i3 has access to faster, more modern memory technology.

Specification Differences

| Specification | Intel Core i3-7320 | Intel Core i5-2400 |

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

| Cores | 2 | 4 |

| Threads | 4 | 4 |

| Base Clock | 4.10 GHz | 3.10 GHz |

| Boost Clock | None | 3.40 GHz |

| TDP | 51 W | 95 W |

| Socket | Intel Socket 1151 | Intel Socket 1155 |

| Architecture | Kaby Lake | Sandy Bridge |

| Process Node | 14 nm | 32 nm |

| Transistors | Not listed | 1,160 million |

| Die Size | Not listed | 216 mm² |

| L3 Cache | 4 MB (shared) | 6 MB (shared) |

| Memory Support | DDR4 | DDR3 |

| Memory Bandwidth | 38.4 GB/s | Not listed |

| Integrated Graphics | Intel HD 630 | Intel HD 2000 |

| Production Status | Active | End-of-life |

| Release Date | January 2, 2017 | January 8, 2011 |

| Part Number | SR358 | SR00Q |

The specification table highlights the generational gap. The i3-7320's 14 nm process allows for a 4.10 GHz base clock with only 51 watts TDP, while the i5-2400's 32 nm process requires 95 watts for a 3.10 GHz base (3.40 GHz boost). The i3's socket change to 1151 and DDR4 support further separate it from the i5's 1155 socket and DDR3 memory. While the i5 has more physical cores and more L3 cache, these advantages are nullified by the i3's superior IPC, clock speed, and memory bandwidth. The i5-2400's transistor count (1,160 million) and die size (216 mm²) are listed, but no comparative data exists for the i3-7320, making a direct transistor-level comparison impossible. Both CPUs lack an unlocked multiplier, so neither offers overclocking headroom.