Intel Core i3-6300 vs Intel Core i5-2400S Comparison

The Verdict

The recorded data shows a clear overall winner: the Intel Core i3-6300 wins all five head-to-head benchmark comparisons against the Intel Core i5-2400S. The i3-6300 leads by roughly 30% in every measured Cinebench test, including both multi-core and single-core workloads. Its average benchmark score of 978 sits slightly above the i5-2400S's 968, placing both in the 26th percentile of all CPUs in the database.

The Core i3-6300 is the appropriate choice for users prioritizing raw compute throughput in both lightly threaded and fully loaded scenarios. The Core i5-2400S, despite having four physical cores to the i3's two, does not translate that core count into a benchmark advantage in any recorded test. It remains usable for legacy DDR3 platforms, but the data does not show a single workload category where it beats the newer part.

Architecture Differences

The two processors come from different Intel eras. The Core i3-6300 uses the Skylake architecture on a 14 nm process, while the Core i5-2400S uses Sandy Bridge on a 32 nm process. The i3-6300 integrates 1,400 million transistors on a 150 mm² die; the i5-2400S integrates 1,160 million transistors on a larger 216 mm² die. The newer process node gives the i3-6300 a density and efficiency advantage that shows up in its 51 W TDP versus the i5-2400S's 65 W TDP.

Core configuration differs significantly. The i3-6300 has 2 cores and 4 threads thanks to Hyper-Threading. The i5-2400S has 4 cores and 4 threads with no simultaneous multithreading. The i3-6300 runs at a fixed 3.80 GHz base clock with no boost clock, while the i5-2400S has a 2.50 GHz base clock and a 3.30 GHz boost clock. Despite the i5's higher maximum clock, it cannot match the i3's per-core speed.

Cache layouts also differ. Both share 64 KB of L1 per core and 256 KB of L2 per core. The L3 cache is 4 MB shared on the i3-6300 versus 6 MB shared on the i5-2400S. The i5's larger L3 does not overcome its older architecture in the recorded benchmarks.

Memory support diverges by platform generation. The i3-6300 uses DDR4 with dual-channel memory and a measured 34.1 GB/s bandwidth. The i5-2400S uses DDR3 with dual-channel memory; no bandwidth figure was recorded in the database. Both support PCIe Gen 3 with 16 CPU lanes. The i3-6300 includes Intel HD 530 integrated graphics, while the i5-2400S includes Intel HD 2000. Neither processor supports ECC memory, and both have locked multipliers. The i3-6300 is currently marked as Active in production, while the i5-2400S is End-of-life.

Where Each One Wins

The Core i3-6300 wins every recorded benchmark category. In multi-core workloads, the i3-6300 scores 340 in Cinebench R15 versus 262 for the i5-2400S, a 29.8% lead. In Cinebench R20 multi-core, the i3-6300 scores 1419 versus 1092, a 29.9% lead. In Cinebench R23 multi-core, the i3-6300 scores 3380 versus 2601, a 30% lead. These results show that the i3's two faster cores with Hyper-Threading outperform the i5's four slower cores, even when all cores are active.

Single-core performance follows the same pattern. The i3-6300 scores 200 in Cinebench R20 single-core versus 154 for the i5-2400S, a 29.9% lead. In Cinebench R23 single-core, the i3-6300 scores 477 versus 367, a 30% lead. The i3-6300 also has a Cinebench R15 single-core score of 52; the i5-2400S has no recorded score for that specific test, but the R20 and R23 results consistently show a ~30% advantage for the newer part.

There is no recorded benchmark where the i5-2400S wins. The i5 does have additional Geekbench scores (1709 multi-core, 593 single-core) that the i3-6300 lacks, so direct comparison on that suite is not available. However, across all overlapping Cinebench tests, the i3-6300 is uniformly ahead. The i5-2400S might appeal to users with existing DDR3 motherboards who want four physical cores without Hyper-Threading, but the data does not support a performance-based argument for it.

FAQ

Q: Which CPU is faster in multi-core workloads?

A: The Intel Core i3-6300. It wins Cinebench R15 multi-core with 340 versus 262, Cinebench R20 multi-core with 1419 versus 1092, and Cinebench R23 multi-core with 3380 versus 2601. That is a consistent 29.8% to 30% lead over the i5-2400S.

Q: Does the i5-2400S's four physical cores beat the i3-6300's two cores?

A: No. Despite having twice the physical core count, the i5-2400S loses every multi-core test. The i3-6300's higher clock speed and newer architecture more than compensate for having only two cores with four threads.

Q: How do the two CPUs compare in single-core performance?

A: The i3-6300 wins by approximately 30%. It scores 200 in Cinebench R20 single-core versus 154 for the i5-2400S, and 477 in Cinebench R23 single-core versus 367.

Q: What are the architectural differences between these two CPUs?

A: The i3-6300 uses Skylake on a 14 nm process with 1,400 million transistors on a 150 mm² die, and it supports DDR4 memory. The i5-2400S uses Sandy Bridge on a 32 nm process with 1,160 million transistors on a 216 mm² die, and it supports DDR3 memory.

Q: What is the TDP difference?

A: The i3-6300 has a 51 W TDP, while the i5-2400S has a 65 W TDP. The newer process node allows the i3 to deliver higher performance while drawing less power under its rated thermal envelope.

Q: Which CPU has a larger L3 cache?

A: The i5-2400S has 6 MB of shared L3 cache, while the i3-6300 has 4 MB. The larger cache does not give the i5 an advantage in any recorded benchmark.

Head-to-Head Benchmarks

The head-to-head results are remarkably consistent. Across five overlapping Cinebench tests, the Intel Core i3-6300 wins all five, with deltas ranging from 29.8% to 30%. The i5-2400S records zero wins.

The largest percentage advantage appears in Cinebench R23. In the multi-core test, the i3-6300 scores 3380 versus 2601, a 30% delta. In the single-core test, the i3-6300 scores 477 versus 367, also a 30% delta. These are the widest margins in the dataset, showing that the newer architecture's advantage holds equally in both fully threaded and single-threaded scenarios.

Cinebench R20 shows nearly identical margins. The multi-core test has the i3-6300 at 1419 versus 1092, a 29.9% delta. The single-core test has the i3-6300 at 200 versus 154, also a 29.9% delta. Cinebench R15 multi-core has the i3-6300 at 340 versus 262, a 29.8% delta, the smallest margin of any recorded comparison but still a substantial lead.

The i3-6300's average benchmark score of 978 places it just ahead of its nearest rivals in the database. Those rivals include the Intel Core i5-5257U at 976 (0.2% behind), the Intel Core i3-4150T at 975 (0.3% behind), the Intel Core i3-4130 at 975 (0.3% behind), and the AMD Athlon X4 840 at 975 (0.3% behind). The i5-2400S's average score of 968 places it near the AMD Ryzen 7 3700U at 968 (0.1% ahead), the Intel Xeon X5570 at 967 (0.1% ahead), and the Intel Celeron N5100 at 966 (0.2% ahead), while it trails the AMD PRO A8-9600 at 971 by 0.3%.

The data indicates that the i3-6300 not only beats the i5-2400S directly but also sits in a slightly stronger competitive position among CPUs with similar average scores. The i3's 978 average is 10 points higher than the i5's 968, a 1% overall gap that extends beyond the Cinebench suite. Both CPUs land at the 26th percentile of all CPUs in the database, indicating that neither is a high-performance part by modern standards, but the i3-6300 is consistently the better performer of the two.

For users building on a modern DDR4 platform, the i3-6300 is the obvious choice from this comparison. For users with an existing DDR3 platform, the i5-2400S offers four physical cores and a higher boost clock, but the benchmark data shows no scenario where that translates into a win. The i3-6300's combination of newer process technology, higher clock speed, and Hyper-Threading gives it a uniform ~30% advantage across all recorded workloads.