Intel Core i3-7300 vs Intel Core i7-5557U Comparison

The Intel Core i3-7300 and Intel Core i7-5557U are both dual-core, four-thread processors, but the benchmark data reveals they are not in the same class. The i3-7300 decisively outperforms the i7-5557U across every single tested workload, with margins that are both consistent and substantial. The i7-5557U, despite its higher-tier branding, is a low-power mobile part that cannot keep pace with the desktop-oriented i3-7300, which wins all five head-to-head comparisons.

Head-to-Head Benchmarks

The most striking result is the uniformity of the i3-7300's victory. In the Cinebench R15 multi-core test, the i3-7300 scores 388 points against the i7-5557U's 270 points, a 43.7% advantage. This gap is not an anomaly; it replicates almost exactly across every other test. In Cinebench R20 multi-core, the i3-7300 scores 1619 versus 1126, a 43.8% lead. The single-core results tell the same story, with the i3-7300 posting 228 points in Cinebench R20 single-core compared to 158 for the i7-5557U, a 44.3% difference.

The newer Cinebench R23 tests confirm this trend. The i3-7300's multi-core score of 3856 is 43.8% higher than the i7-5557U's 2682. Even in single-core performance, where clock speed is paramount, the i3-7300 maintains a 43.9% lead with 544 points versus 378. This consistency across four different Cinebench versions indicates a fundamental performance gap rather than a workload-specific quirk. The i7-5557U does have an edge in one area not captured in the head-to-head list: it boasts a Geekbench multi-core score of 2099 and a single-core score of 1060, while the i3-7300 has no Geekbench results in the data. However, this absence does not change the fact that in all directly comparable tests, the i3-7300 is the clear winner.

The average benchmark scores align with these findings. The i3-7300 has an average benchmark score of 1115, while the i7-5557U sits at 1110. This near-parity in overall average is somewhat misleading, as it is likely influenced by the different benchmark suites each CPU was tested with. Looking at the nearest rivals for the i3-7300, it sits at 0% deltaPct against the AMD Ryzen 3 1200 and is 0.4% ahead of the i7-5557U. For the i7-5557U, its nearest rival is the Intel Xeon E5630 at 0% deltaPct, and it is 0.1% behind the Intel Xeon E5-2609 v3. These figures place both CPUs in the 31st percentile of all processors, indicating they are both entry-level performers, but the head-to-head results show a clear hierarchy between them.

FAQ

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

A: The Intel Core i3-7300 is significantly faster. It wins the Cinebench R15 multi-core test with a score of 388 versus 270 for the i7-5557U, a 43.7% lead. In Cinebench R23 multi-core, the i3-7300 scores 3856 against 2682, a 43.8% advantage.

Q: Is the i7-5557U better for single-core tasks?

A: No. The i3-7300 also dominates single-core tests. In Cinebench R20 single-core, the i3-7300 scores 228 compared to 158 for the i7-5557U, a 44.3% difference. The i3-7300 also leads in Cinebench R23 single-core with 544 versus 378.

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

A: Yes, both are dual-core processors with four threads. They also share the same L1 cache (64 KB per core), L2 cache (256 KB per core), and L3 cache (4 MB shared).

Q: What is the difference in their power consumption?

A: The i3-7300 has a TDP of 51 watts, while the i7-5557U has a TDP of 28 watts. This indicates the i7-5557U is designed for more power-sensitive mobile environments.

Q: What is the release date difference between these two?

A: The i3-7300 was released on January 2, 2017, while the i7-5557U was released earlier on February 28, 2015. The i7-5557U is also marked as end-of-life, whereas the i3-7300 is still active in production.

Q: Which CPU has a higher clock speed?

A: The i3-7300 has a base clock of 4.00 GHz, which is higher than the i7-5557U's base clock of 3.10 GHz. The i7-5557U does offer a boost clock of 3.40 GHz, but the i3-7300 has no boost clock listed, meaning it runs at a constant 4.00 GHz.

Architecture Differences

The two CPUs belong to different Intel microarchitectures and are built for different segments. The i3-7300 is based on the Kaby Lake architecture (generation "Core i3 (Kaby Lake)") and targets the desktop market with an Intel Socket 1151. In contrast, the i7-5557U is based on the older Broadwell architecture (generation "Core i7 (Broadwell-U)") and is a mobile part featuring Intel BGA 1168. Both are built on the same 14 nm process node, but the i7-5557U provides more physical details, with 1,900 million transistors on a 133 mm² die. The i3-7300's transistor count and die size are not listed.

The memory support is another key divider. The i3-7300 supports DDR4 memory with a dual-channel bus and a higher theoretical memory bandwidth of 38.4 GB/s. The i7-5557U supports the older DDR3 standard, also dual-channel, but with a lower memory bandwidth of 29.9 GB/s. The integrated graphics differ as well; the i3-7300 comes with Intel HD 630, while the i7-5557U features the higher-tier Intel Iris 6100. PCIe connectivity also differs, with the i3-7300 offering Gen 3 with 16 lanes (CPU only), whereas the i7-5557U provides Gen 2 with 12 lanes (CPU only). Neither CPU supports ECC memory, and both have locked multipliers.

The Verdict

The data is unambiguous: the Intel Core i3-7300 is the superior processor for performance. It wins every benchmark where both were tested, with margins ranging from 43.7% to 44.3%. For any user prioritizing computational speed in Cinebench workloads, the i3-7300 is the only logical choice between these two. Its higher base clock of 4.00 GHz and newer Kaby Lake architecture deliver a consistent performance advantage over the i7-5557U's older Broadwell design and lower 3.10 GHz base clock.

However, the i7-5557U is not without merit. Its significantly lower TDP of 28 watts compared to 51 watts makes it a far more power-efficient option. This is a critical factor for mobile devices where battery life and thermal management are paramount. The i7-5557U is an end-of-life mobile processor, while the i3-7300 is an active desktop part. The i7-5557U also has the distinction of a launch MSRP of $426, which is a notable figure for a mobile chip. The choice depends entirely on the use case: raw performance for a desktop points to the i3-7300, while power efficiency for a laptop points to the i7-5557U. For a fixed desktop environment, the i3-7300's performance is decisive.

Specification Differences

The two processors differ on almost every key specification except for core count, thread count, and cache hierarchy. The table below highlights the critical differences:

| Specification | Intel Core i3-7300 | Intel Core i7-5557U |

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

| Base Clock | 4.00 GHz | 3.10 GHz |

| Boost Clock | None | 3.40 GHz |

| TDP | 51 W | 28 W |

| Socket | Intel Socket 1151 | Intel BGA 1168 |

| Architecture | Kaby Lake | Broadwell |

| Process Node | 14 nm | 14 nm |

| Transistors | Not listed | 1,900 million |

| Die Size | Not listed | 133 mm² |

| Memory Support | DDR4 | DDR3 |

| Memory Bandwidth | 38.4 GB/s | 29.9 GB/s |

| PCIe | Gen 3, 16 Lanes | Gen 2, 12 Lanes |

| Integrated Graphics | Intel HD 630 | Intel Iris 6100 |

| Market Segment | Desktop | Mobile |

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

| Release Date | 2017-01-02 | 2015-02-28 |

| Part Number | SR359 | SR26E |

Where Each One Wins

The performance landscape is starkly one-sided, but the use cases are not. The Intel Core i3-7300 wins in every computational benchmark recorded in the head-to-head data. It is the clear choice for applications that demand high single-threaded and multi-threaded performance, as evidenced by its 43.7% lead in Cinebench R15 multi-core and 44.3% lead in Cinebench R20 single-core. This makes it suitable for desktop users who run CPU-intensive tasks like video encoding, 3D rendering, or complex spreadsheet calculations, where its 4.00 GHz base clock and newer architecture provide a significant edge.

The Intel Core i7-5557U wins in the domain of power efficiency and portability. Its 28-watt TDP is nearly half that of the i3-7300's 51-watt TDP, making it the only viable option for ultra-thin laptops or compact devices where heat dissipation and battery life are critical constraints. Its integrated Intel Iris 6100 graphics are also a step up from the HD 630 in the i3-7300, potentially offering better performance in light gaming or media tasks for mobile users. The i7-5557U's lower memory bandwidth (29.9 GB/s) and older DDR3 support are acceptable trade-offs for its power savings. While it loses all head-to-head benchmarks, it wins in the mobile market segment where the i3-7300 cannot compete due to its desktop socket and higher power draw.