Intel Core i5-4430S vs Intel Core i5-6400 Comparison

Where Each One Wins

The benchmark split between these two quad-core processors is unusually clean. The Intel Core i5-4430S takes six of the eight recorded head-to-head tests, while the Intel Core i5-6400 wins only two. Yet the two wins for the newer chip are not trivial: they are the Geekbench tests, and one of them is by a wide margin.

The i5-4430S dominates every Cinebench workload. In Cinebench R15 multicore, it scores 373 against 364 for the i5-6400, a 2.4% advantage. The single-core R15 result is 52 versus 51, a 1.9% edge. The pattern repeats in R20 and R23, with the i5-4430S leading by 2.3% to 2.6% in every case. This is a consistent, if modest, sweep across the entire Cinebench suite.

The i5-6400, by contrast, wins decisively in Geekbench. The multicore result is 3134 against 2773, a 13% lead. The single-core result is 1048 against 980, a 6.9% advantage. These are not marginal differences. The Geekbench tests appear to reward the newer architecture in ways that Cinebench does not.

What does this imply? The i5-4430S, despite being older and built on a larger process node, holds a slight edge in rendering-style workloads. The i5-6400, with its newer Skylake architecture, pulls ahead in the more varied, memory-sensitive Geekbench tests. Users prioritizing Cinebench-style rendering would prefer the i5-4430S. Those looking at general system responsiveness, as measured by Geekbench, would see the i5-6400 as the stronger choice.

Architecture Differences

The two chips come from different Intel generations and different manufacturing processes. The i5-6400 is Skylake, built on a 14 nm process. The i5-4430S is Haswell, built on a 22 nm process. Both are quad-core, four-thread desktop parts with the same 65 W TDP, but the underlying designs diverge significantly.

The process node difference is the most obvious architectural gap. The 14 nm Skylake die is physically smaller in transistor density terms, though the recorded die size for both is 177 mm². The i5-4430S lists 1,400 million transistors, while the i5-6400 does not have a transistor count in the database. The newer process allows Skylake to operate at a higher boost clock: 3.30 GHz versus 3.20 GHz for the Haswell part. Base clocks are identical at 2.70 GHz.

Cache configurations are the same on paper: 64 KB L1 per core, 256 KB L2 per core, and 6 MB shared L3. The memory support differs, however. The i5-6400 uses DDR4 with a recorded memory bandwidth of 34.1 GB/s. The i5-4430S uses DDR3, and its memory bandwidth is not recorded in the database. Both run dual-channel memory.

The integrated graphics also differ. The i5-6400 carries HD Graphics 530, while the i5-4430S has Intel HD 4600. The sockets are incompatible: the i5-6400 uses Intel Socket 1151, the i5-4430S uses Intel Socket 1150. PCIe support is listed as Gen 3 with 16 lanes for the i5-6400, while the i5-4430S is simply listed as Gen 3.

The release dates are separated by roughly two years. The i5-4430S launched in June 2013, the i5-6400 in July 2015. The i5-6400 has a recorded launch MSRP of $182, while the i5-4430S has no launch price in the database. Both are locked multipliers, and neither supports ECC memory.

Head-to-Head Benchmarks

The most striking result in the head-to-head data is the Geekbench multicore test. The i5-6400 scores 3134, the i5-4430S scores 2773. That is a 13% delta in favor of the Skylake part. For a comparison between two quad-core chips with identical base clocks and similar boost clocks, a 13% gap is substantial. It suggests the newer architecture extracts significantly more performance from the same core and thread count in this particular workload.

The Geekbench single-core test tells a similar story, though with a smaller margin. The i5-6400 scores 1048, the i5-4430S scores 980, a 6.9% lead. Single-core performance is often a good proxy for everyday responsiveness, and here the Skylake chip is clearly ahead.

The Cinebench results flip the narrative. In Cinebench R15 multicore, the i5-4430S scores 373 against 364 for the i5-6400, a 2.4% edge. The single-core R15 result is 52 versus 51, a 1.9% lead. The R20 multicore test shows 1558 versus 1517, a 2.6% gap. The R20 single-core test shows 219 versus 214, a 2.3% gap. The R23 multicore test shows 3710 versus 3614, a 2.6% gap. The R23 single-core test shows 523 versus 510, a 2.5% gap.

The consistency of the Cinebench results is notable. Every single Cinebench test, across three different versions of the benchmark, favors the i5-4430S by roughly the same margin. This is not a fluke or a single-test anomaly. The Haswell chip appears to have a small but real advantage in this rendering workload.

The average benchmark scores reflect the split. The i5-6400 has an average score of 1307, the i5-4430S has 1274. The i5-6400 sits at the 35th percentile of all CPUs, as does the i5-4430S. The nearest rivals for the i5-6400 include the AMD Opteron 6328 at 1304 (0.2% delta) and the Intel Core i7-3770T at 1314 (-0.5% delta). The nearest rivals for the i5-4430S include the Intel Atom x7425E at 1273 (0.1% delta) and the Intel Core i5-4670T at 1271 (0.2% delta).

Specification Differences

The two processors share several core specifications: both have 4 cores, 4 threads, a 2.70 GHz base clock, 65 W TDP, 64 KB L1 per core, 256 KB L2 per core, and 6 MB shared L3. The differences are concentrated in a few key areas.

The boost clock differs: the i5-6400 reaches 3.30 GHz, the i5-4430S reaches 3.20 GHz. The process node differs: 14 nm for the i5-6400, 22 nm for the i5-4430S. The transistor count is recorded only for the i5-4430S at 1,400 million. The socket differs: Socket 1151 for the i5-6400, Socket 1150 for the i5-4430S. The memory support differs: DDR4 for the i5-6400, DDR3 for the i5-4430S. The memory bandwidth is recorded only for the i5-6400 at 34.1 GB/s. The integrated graphics differ: HD Graphics 530 for the i5-6400, Intel HD 4600 for the i5-4430S. The release dates differ: July 2015 for the i5-6400, June 2013 for the i5-4430S. The launch MSRP is recorded only for the i5-6400 at $182. The part numbers differ: SR2L7 for the i5-6400, SR14M for the i5-4430S.

FAQ

Q: Which processor is faster in Cinebench tests?

A: The Intel Core i5-4430S wins all six Cinebench tests, with margins ranging from 1.9% in R15 single-core to 2.6% in R20 and R23 multicore.

Q: Which processor is faster in Geekbench tests?

A: The Intel Core i5-6400 wins both Geekbench tests. It leads by 13% in multicore (3134 versus 2773) and by 6.9% in single-core (1048 versus 980).

Q: Do the two processors have the same core and thread count?

A: Yes, both have 4 cores and 4 threads. They also share the same base clock of 2.70 GHz and the same 65 W TDP.

Q: What are the main architectural differences?

A: The i5-6400 uses the Skylake architecture on a 14 nm process, while the i5-4430S uses Haswell on a 22 nm process. The i5-6400 supports DDR4 memory, the i5-4430S supports DDR3.

Q: Which processor has a higher boost clock?

A: The i5-6400 has a boost clock of 3.30 GHz, while the i5-4430S has a boost clock of 3.20 GHz.

Q: Are the sockets interchangeable?

A: No. The i5-6400 uses Intel Socket 1151, while the i5-4430S uses Intel Socket 1150. They are not compatible with the same motherboards.

The Verdict

The data presents a clear split. The Intel Core i5-4430S is the better choice for Cinebench-style rendering workloads. It wins every Cinebench test by a consistent margin, and its average benchmark score of 1274 is only slightly below the i5-6400's 1307. The i5-4430S also has the advantage of a lower boost clock requirement, though the difference is small.

The Intel Core i5-6400 is the better choice for Geekbench-style general performance. Its 13% multicore lead and 6.9% single-core lead are substantial, and its average benchmark score of 1307 is higher overall. The i5-6400 also brings a newer architecture, a smaller process node, DDR4 memory support, and a higher boost clock.

The choice depends on the workload. For rendering and Cinebench-heavy tasks, the i5-4430S is the data-backed pick. For general system performance as measured by Geekbench, the i5-6400 is clearly ahead. The i5-6400 also offers the newer platform with DDR4 support, which may matter for system longevity. The i5-4430S, despite being older, holds its own in rendering and offers a lower-cost path for users already on Socket 1150. The recorded data does not show a universal winner, only a workload-dependent one.