Intel Core i3-4340 vs Intel Core i7-4558U Comparison

The Intel Core i7-4558U and the Intel Core i3-4340 are both Haswell-era processors with two cores and four threads, but they target fundamentally different market segments. The i7-4558U is a mobile chip designed for laptops, while the i3-4340 is a desktop part. The benchmark data shows a clear and consistent performance gap: the i3-4340 wins every recorded head-to-head comparison. However, the i7-4558U holds advantages in power efficiency and integration, making the choice highly dependent on the intended use case.

Where Each One Wins

The data is unambiguous in terms of raw compute performance. Across all five shared benchmark tests, the Intel Core i3-4340 is the winner. The biggest deltas are seen in multi-core workloads, where the desktop chip's higher sustained clock speeds pay off. In Cinebench R15 multi-core, the i3-4340 scores 300 against 255 for the i7-4558U, a 15% lead. This pattern repeats in Cinebench R20 multi-core, with 1252 versus 1063, again a 15.1% advantage. The single-core tests show a similar margin: Cinebench R20 single-core is 176 versus 149 (15.3% ahead), and Cinebench R23 single-core is 421 versus 357 (15.2% ahead).

The i7-4558U does not win any of the head-to-head tests. Its strengths lie elsewhere. The mobile chip has a significantly lower TDP of 28 watts compared to 54 watts for the desktop part. This makes it the clear choice for thermally constrained, battery-powered systems. The i7-4558U also integrates Intel HD 5100 graphics, while the i3-4340 uses the older Intel HD 4600. In the context of the database, the i7-4558U's average benchmark score of 1038 is competitive with its nearest rivals, including the AMD A8-7680 (1036) and AMD A10-7890K (1035), showing it is not a weak performer for its class. The i3-4340, with an average score of 1026, sits similarly among its peers like the Intel Processor N150 (1025) and Intel Core i7-5650U (1027). Neither chip is a performance outlier; both land in the 28th percentile of all CPUs.

The Verdict

The choice between these two processors is dictated by platform and power constraints, not by raw performance. For any workload where maximum compute throughput is the sole criterion, the Intel Core i3-4340 is the definitive pick. It leads by roughly 15% in every single benchmark recorded. A user building or upgrading a desktop system with a standard Socket 1150 motherboard should choose the i3-4340 without hesitation. Its higher base clock of 3.60 GHz (versus 2.80 GHz) and lack of a boost clock dependency provide a consistent performance advantage in both single-threaded and multi-threaded tasks.

The Intel Core i7-4558U is the appropriate choice for a laptop or a compact, low-power system where the 28-watt TDP is a hard limit. Its performance is not dramatically worse; it trails by 15%, which is noticeable but not crippling. The mobile chip also benefits from a smaller die size (118 mm² versus 177 mm²) and fewer transistors (1,300 million versus 1,400 million), which contributes to its efficiency. For a user who needs a capable processor in a thin and light chassis, the i7-4558U is the only viable option between the two. The i3-4340, with its 54-watt TDP and desktop socket, is not suitable for such applications. In short: pick the i3-4340 for desktop performance, pick the i7-4558U for mobile efficiency.

Head-to-Head Benchmarks

The recorded head-to-head data covers five Cinebench tests, and the Intel Core i3-4340 wins all of them. The smallest margin is in Cinebench R15 multi-core, where the i3-4340 scores 300 and the i7-4558U scores 255, a delta of 15%. The largest margin is in Cinebench R20 single-core, where the i3-4340 scores 176 and the i7-4558U scores 149, a delta of 15.3%. These consistent margins suggest a fundamental clock-speed advantage rather than a single-workload quirk.

In Cinebench R20 multi-core, the i3-4340's 1252 score is 15.1% higher than the i7-4558U's 1063. The same 15.1% delta appears in Cinebench R23 multi-core, with scores of 2983 and 2532 respectively. The single-core results are equally consistent, with Cinebench R23 single-core showing a 15.2% lead for the i3-4340 (421 versus 357). The data does not include a Geekbench comparison, but the Cinebench suite alone provides a robust picture. The i3-4340's fixed 3.60 GHz clock, with no boost variability, delivers a steady advantage over the i7-4558U's base 2.80 GHz and 3.30 GHz boost. The i7-4558U cannot compensate for this deficit in any of the recorded tests.

FAQ

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

A: The Intel Core i3-4340 is faster in all multi-core tests. In Cinebench R23 multi-core, it scores 2983 versus 2532 for the i7-4558U, a 15.1% advantage.

Q: Does the Intel Core i7-4558U win any benchmark?

A: No. The head-to-head data shows zero wins for the i7-4558U and five wins for the i3-4340 across all recorded Cinebench tests.

Q: What is the main advantage of the i7-4558U over the i3-4340?

A: The primary advantage is power efficiency. The i7-4558U has a TDP of 28 watts, while the i3-4340 has a TDP of 54 watts, making the mobile chip suitable for laptops and low-power systems.

Q: Do both processors have the same core and thread configuration?

A: Yes, both the Intel Core i7-4558U and the Intel Core i3-4340 have 2 cores and 4 threads.

Q: Which processor has a higher base clock speed?

A: The Intel Core i3-4340 has a base clock of 3.60 GHz, which is higher than the i7-4558U's base clock of 2.80 GHz. The i7-4558U does have a boost clock of 3.30 GHz, but the i3-4340 has no boost clock.

Q: Are the integrated graphics different between the two?

A: Yes. The i7-4558U features Intel HD 5100 graphics, while the i3-4340 features Intel HD 4600.

Architecture Differences

Both processors are built on Intel's Haswell architecture and use a 22 nm process node from Intel's own foundry. The core microarchitecture is the same, but the physical implementations differ substantially. The i7-4558U, codenamed Haswell-ULT, is designed for ultra-low-power mobile devices. It has a die size of 118 mm² and contains 1,300 million transistors. The i3-4340, codenamed Haswell, is a desktop part with a larger die size of 177 mm² and 1,400 million transistors. This larger die area accommodates the desktop-oriented design and the higher TDP of 54 watts.

The memory support is identical in type (DDR3), but the i3-4340 explicitly supports dual-channel memory, while the i7-4558U's memory bus is not specified in the data. The i3-4340 also supports PCIe Gen 3, a feature not listed for the mobile chip. The integrated graphics differ, with the i7-4558U using the more advanced Intel HD 5100 and the i3-4340 using Intel HD 4600. Neither chip supports ECC memory, and both have locked multipliers, preventing overclocking. The socket types are fundamentally different: the i7-4558U uses Intel BGA 1168, which is soldered to the motherboard, while the i3-4340 uses Intel Socket 1150, which is a standard desktop socket.

Specification Differences

The most significant specification difference is TDP. The i7-4558U is rated at 28 watts, while the i3-4340 is rated at 54 watts. This directly impacts cooling requirements and system form factor. Clock speeds also differ notably: the i7-4558U has a base clock of 2.80 GHz and a boost clock of 3.30 GHz, whereas the i3-4340 has a fixed base clock of 3.60 GHz with no boost capability. The sockets are incompatible, with the mobile part using BGA 1168 and the desktop part using Socket 1150.

The physical characteristics diverge as well. The i7-4558U has a smaller die (118 mm²) and fewer transistors (1,300 million) compared to the i3-4340 (177 mm², 1,400 million). The integrated graphics are different, with the i7-4558U featuring Intel HD 5100 and the i3-4340 featuring Intel HD 4600. The i3-4340 lists PCIe Gen 3 support and dual-channel memory, while the i7-4558U does not list these in the database. Both chips share the same cache hierarchy: 64 KB L1 per core, 256 KB L2 per core, and 4 MB shared L3. Their release dates are close, with the i7-4558U released on June 3, 2013, and the i3-4340 on August 31, 2013. Neither has a recorded launch MSRP. Both are in the 28th percentile of all CPUs, and their average benchmark scores are similar (1038 for the i7-4558U, 1026 for the i3-4340), but the distribution of wins heavily favors the desktop chip.