CPU Comparison

The Intel Core i5-2400 and Intel Core i5-3550 are both 4-core, 4-thread desktop processors on the Intel Socket 1155 platform, but the data shows they are not equals. The i5-3550 wins every single head-to-head benchmark in the pack, with margins ranging from 19.5% to 19.8% across Cinebench tests. If you are choosing between these two end-of-life parts, the i5-3550 is the clear performance pick, offering roughly one-fifth more multi-threaded and single-threaded throughput. The i5-2400, meanwhile, finds its place only in systems where its lower average benchmark score of 1187 (vs 1178 for the i5-3550) is somehow preferable, which the data does not support. The verdict is straightforward: the i5-3550 is the superior processor in every measured category.

The Verdict

The benchmark results are unambiguous: the Intel Core i5-3550 is the faster CPU in every single test recorded. Across five Cinebench workloads, the i5-3550 consistently beats the i5-2400 by roughly 19-20%. Specifically, the i5-3550 scores 410 in Cinebench R15 multicore versus 329 for the i5-2400, and 4073 in Cinebench R23 multicore versus 3272. Single-core performance follows the same pattern, with the i5-3550 posting 575 in Cinebench R23 single-core versus 462 for the i5-2400. The data shows zero wins for the i5-2400 in the head-to-head comparison.

For a builder today, the choice depends on what you are doing with the system. If you need the fastest possible performance from an older Socket 1155 platform, the i5-3550 is the only rational pick. Its 3.30 GHz base and 3.70 GHz boost clocks, combined with the 22 nm Ivy Bridge architecture, deliver a decisive advantage over the i5-2400's 3.10 GHz base and 3.40 GHz boost on 32 nm Sandy Bridge. The i5-2400's only statistical advantage is its average benchmark score of 1187, which is 0.7% higher than the i5-3550's 1178, but this is a meaningless aggregate figure when every direct comparison shows the i5-3550 winning by a wide margin.

There is no scenario in the data where the i5-2400 is the better choice. Its lower clocks, older architecture, and identical core/thread count mean it loses all compute-bound workloads. The i5-3550 also has a lower TDP of 77 Watts versus 95 Watts for the i5-2400, making it both faster and more power-efficient. If you are on a strict budget and cannot afford any upgrade, the i5-2400 will still work, but the data suggests you are leaving about 20% performance on the table. Choose the i5-3550 unless you already own the i5-2400 and cannot justify a swap.

FAQ

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

A: The Intel Core i5-3550 is faster in every multi-core test. It scores 410 in Cinebench R15 multicore versus 329 for the i5-2400, 1710 in Cinebench R20 multicore versus 1374, and 4073 in Cinebench R23 multicore versus 3272. The delta is consistently around 19.6-19.8%.

Q: How do the single-core scores compare?

A: The i5-3550 leads in single-core performance as well. In Cinebench R20 single-core, it scores 241 versus 194 for the i5-2400, and in Cinebench R23 single-core, it scores 575 versus 462. That is a 19.5% and 19.7% advantage, respectively.

Q: Do both processors have the same number of cores and threads?

A: Yes, both have 4 cores and 4 threads. Neither supports hyper-threading, and both are locked processors (multiplierUnlocked is false for both). The performance difference comes entirely from architectural and clock improvements, not from core count.

Q: What is the difference in power consumption?

A: The i5-3550 has a TDP of 77 Watts, while the i5-2400 has a TDP of 95 Watts. This means the i5-3550 is not only faster but also draws less power, making it the more efficient choice for any system.

Q: Which processor is newer?

A: The i5-3550 was released on 2012-04-28, while the i5-2400 was released on 2011-01-08. The i5-3550 is the newer part by over a year, which explains its architectural advantages.

Q: Are they compatible with the same motherboards?

A: Yes, both use the Intel Socket 1155. However, they belong to different architectures, the i5-2400 is Sandy Bridge and the i5-3550 is Ivy Bridge, so motherboard BIOS compatibility may vary, but the physical socket is identical.

Architecture Differences

The core architectural split between these two CPUs is the generational leap from Sandy Bridge to Ivy Bridge. The i5-2400 is built on the 32 nm process node, while the i5-3550 uses the newer 22 nm node. This shrink is evident in the transistor counts: the i5-2400 packs 1,160 million transistors on a 216 mm² die, whereas the i5-3550 crams 1,400 million transistors onto a smaller 160 mm² die. The smaller, denser process allows the i5-3550 to run at higher clocks while consuming less power.

Both chips share the same fundamental layout: 4 cores, 4 threads, 64 KB of L1 cache per core, 256 KB of L2 cache per core, and 6 MB of shared L3 cache. Memory support is also identical, DDR3 with a dual-channel bus, and neither supports ECC memory. PCIe connectivity is the same on paper: Gen 3 with 16 lanes (CPU only). The integrated graphics differ, though: the i5-2400 uses Intel HD 2000, while the i5-3550 steps up to Intel HD 2500.

The architectural improvements in Ivy Bridge over Sandy Bridge are the primary reason for the performance gap. The 22 nm process enables higher clock speeds at lower voltages, and the i5-3550 takes advantage of that with a 3.30 GHz base and 3.70 GHz boost, compared to the i5-2400's 3.10 GHz base and 3.40 GHz boost. The i5-3550's memory bandwidth is rated at 25.6 GB/s, a figure not listed for the i5-2400, suggesting a refined memory controller. Both parts are end-of-life desktop processors, but the i5-3550 is the newer, more advanced design.

Specification Differences

The two processors differ in several key specification fields. The i5-3550 has a base clock of 3.30 GHz versus 3.10 GHz for the i5-2400, and a boost clock of 3.70 GHz versus 3.40 GHz. The i5-3550's TDP is 77 Watts, significantly lower than the i5-2400's 95 Watts. The process node is 22 nm for the i5-3550 and 32 nm for the i5-2400, with corresponding transistor counts of 1,400 million versus 1,160 million, and die sizes of 160 mm² versus 216 mm².

The i5-3550 has a listed memory bandwidth of 25.6 GB/s, while the i5-2400 does not have a figure in the data. Integrated graphics differ: the i5-3550 comes with Intel HD 2500, the i5-2400 with Intel HD 2000. Release dates are 2012-04-28 for the i5-3550 and 2011-01-08 for the i5-2400. The i5-3550 has a launch MSRP of $194; the i5-2400 has no launch MSRP listed. Part numbers are SR0P0 for the i5-3550 and SR00Q for the i5-2400.

Both are on the same socket (Intel Socket 1155), same architecture family (Core i5), same core/thread count (4/4), same cache hierarchy (64 KB L1 per core, 256 KB L2 per core, 6 MB shared L3), same memory type (DDR3, dual-channel), no ECC support, same PCIe configuration (Gen 3, 16 lanes), and both have locked multipliers. The differences are all in clocks, power, process, graphics, and memory bandwidth.

Head-to-Head Benchmarks

The head-to-head data is a clean sweep for the i5-3550, which wins all 5 recorded comparisons. In Cinebench R15 multicore, the i5-3550 scores 410 against 329 for the i5-2400, a delta of -19.8% (where the negative sign indicates the i5-2400 is behind). Cinebench R20 multicore shows 1710 versus 1374, a 19.6% gap. Single-core results are equally lopsided: Cinebench R20 single-core is 241 versus 194 (19.5% delta), and Cinebench R23 single-core is 575 versus 462 (19.7% delta).

The largest margin is in Cinebench R15 multicore at 19.8%, while the smallest is in Cinebench R20 single-core at 19.5%. This consistency across workloads, from single-threaded to multi-threaded, indicates that the i5-3550's advantage is not workload-specific but rather a fundamental clock-for-clock and architecture-for-architecture superiority. The i5-2400's best result is its Geekbench single-core score of 666 and multi-core score of 2011, but the i5-3550 does not have Geekbench entries in the head-to-head table, so those cannot be directly compared.

Looking at the average benchmark scores, the i5-2400 has an average of 1187, while the i5-3550 has an average of 1178. This aggregate metric slightly favors the i5-2400, but it is an artifact of which tests are included in the average. The direct head-to-head tests, which use identical Cinebench workloads for both chips, all favor the i5-3550 by roughly 20%. The i5-2400's nearest rivals (i5-4460T at 1190, Opteron 6234 at 1191, i7-8665UE at 1193, i3-4170 at 1193) all score within 0.5% of its average, while the i5-3550's rivals (i5-4440 at 1179, i3-7320 at 1173, i7-3635QM at 1170) are also clustered tightly, with the i5-2400 itself appearing as a rival at 1187 with a delta of -0.7%.

Where Each One Wins

Based strictly on the benchmark data, the i5-3550 wins everywhere that matters. It is ahead by 19.5-19.8% in all Cinebench tests, covering both single-core and multi-core workloads. This makes it the superior choice for any CPU-bound task: rendering, encoding, compilation, or general desktop responsiveness. If you are building a system for productivity or light gaming on a Socket 1155 platform, the i5-3550 is the pick. Its lower TDP (77W vs 95W) also means it runs cooler and puts less strain on the power delivery, which is an operational advantage.

The i5-2400 has no benchmark wins in the head-to-head data. Its only statistical edge is the average benchmark score of 1187 versus 1178, but this is a narrow 0.7% difference that does not reflect real-world performance in any specific test. The i5-2400's nearest rivals are all slightly above or below its average score, but none of them are the i5-3550, which is listed as the i5-3550's rival with a delta of -0.7%. This means the i5-2400's average is dragged up by tests where the i5-3550 was not measured, not because it is genuinely faster.

In practical terms, the i5-2400 remains a functional quad-core processor, but the data shows it is outclassed by its successor. The i5-3550 offers a ~20% performance uplift across the board, a 18 Watt TDP reduction, and a newer integrated GPU (HD 2500 vs HD 2000). There is no use case in the FACT PACK where the i5-2400 comes out ahead. If you already own the i5-2400, it will still run modern software, but if you are sourcing parts, the i5-3550 is the definitive choice for Socket 1155 builds.