Intel Core i3-5020U vs Intel Xeon E5520 Comparison

Head-to-Head Benchmarks

The benchmark data is unambiguous: the Intel Xeon E5520 wins every recorded comparison, and it does so by a consistent margin. Across five Cinebench tests, the Xeon leads the Core i3-5020U by roughly 13% in every single instance. The narrowest gap is in Cinebench R23 multi-core, where the Xeon scores 2155 against the i3's 1876, a 12.9% advantage. The widest gaps, 13.4%, appear in Cinebench R15 multi-core (217 vs 188) and Cinebench R20 single-core (127 vs 110).

The single-core results are particularly telling. The Xeon E5520 posts a Cinebench R20 single-core score of 127, beating the i3-5020U's 110 by 13.4%. In Cinebench R23 single-core, the Xeon scores 304 versus 264, a 13.2% lead. This is noteworthy because the i3-5020U is a much newer design with a smaller process node, yet it cannot outrun the older Xeon even on lightly threaded workloads. The Xeon's higher base clock of 2.27 GHz versus 2.20 GHz, combined with its boost clock of 2.53 GHz, likely explains part of this, though the architecture differences also matter.

Multi-core scaling tells the same story. The Xeon doubles the core count (4 versus 2) and doubles the thread count (8 versus 4), which should produce a larger advantage than the observed 13%. The data shows a 13% gap in Cinebench R20 multi-core (905 vs 787) and a 13% gap in Cinebench R23 multi-core (2155 vs 1876). This suggests that the i3-5020U's newer Broadwell architecture is more efficient per clock, but the Xeon's extra cores and threads still carry the day.

The overall average benchmark scores reinforce the pattern. The i3-5020U averages 757 across its benchmark suite, while the Xeon E5520 averages 742. That difference is small, about 2%, and the nearest rivals for each part confirm they sit in the same performance tier. The i3-5020U's nearest rival, the Intel Xeon E5450, scores 756, a delta of 0.1%. The Xeon E5520's nearest rival, the AMD Phenom II X4 B97, scores 741, also a delta of 0.1%. Both parts occupy the same percentile rank, 20th among all CPUs in the database.

Architecture Differences

The two processors come from different eras and different design philosophies. The Core i3-5020U is built on Broadwell, specifically the Broadwell-U codename, using a 14 nm process node. It integrates 1,300 million transistors on an 82 mm² die. The Xeon E5520 uses the older Nehalem architecture, codenamed Gainestown, on a 45 nm process. It packs 731 million transistors on a much larger 263 mm² die. The process node gap is substantial, 14 nm versus 45 nm, which explains why the i3 achieves similar performance with far fewer resources.

Cache configurations differ sharply. The i3-5020U has 64 KB of L1 per core and 256 KB of L2 per core, with a shared 3 MB L3 cache. The Xeon E5520 matches the per-core L1 and L2 sizes, but its shared L3 cache expands to 8 MB, more than double the i3's allocation. This larger cache likely helps the Xeon in multi-threaded workloads where repeated data access patterns benefit from more on-die storage.

Memory support diverges as well. Both parts support DDR3, but the i3-5020U uses a dual-channel memory bus with 25.6 GB/s of bandwidth. The Xeon E5520 uses a triple-channel memory bus, though the database does not record a bandwidth figure for it. Triple-channel configuration generally provides higher theoretical bandwidth, which can matter for server workloads. The Xeon also supports ECC memory, while the i3 does not. That distinction is critical for workstation and server deployments where data integrity is paramount.

The integrated GPU is another major split. The i3-5020U includes Intel HD 5500 graphics, making it a complete package for a mobile system without a discrete graphics card. The Xeon E5520 has no integrated graphics at all, requiring a separate GPU for any display output. This reflects their market segments: the i3 is a mobile part, while the Xeon targets server and workstation environments where a GPU is assumed to be present.

PCIe support also differs. The i3-5020U provides Gen 2 with 12 lanes from the CPU. The Xeon E5520 provides Gen 2 as well, but the database does not list a lane count. Both are older PCIe generations, which limits expansion options compared to modern platforms, but the Xeon's server-oriented design typically includes more robust I/O connectivity.

The sockets are incompatible. The i3-5020U uses Intel BGA 1168, a soldered mobile socket, while the Xeon E5520 uses Intel Socket 1366, a land grid array socket for server motherboards. This means neither part can be swapped into the other's platform. The i3 is permanently attached to its motherboard, while the Xeon is replaceable but only within Socket 1366 boards.

FAQ

Q: Which processor has more cores and threads?

A: The Intel Xeon E5520 has 4 cores and 8 threads, double the Core i3-5020U's 2 cores and 4 threads.

Q: Does the Core i3-5020U have integrated graphics?

A: Yes, the i3-5020U includes Intel HD 5500 graphics. The Xeon E5520 has no integrated graphics.

Q: Which CPU supports ECC memory?

A: Only the Intel Xeon E5520 supports ECC memory. The Core i3-5020U does not.

Q: What is the process node difference between the two?

A: The Core i3-5020U is built on a 14 nm process, while the Xeon E5520 uses a 45 nm process.

Q: How much L3 cache does each processor have?

A: The Core i3-5020U has 3 MB of shared L3 cache, while the Xeon E5520 has 8 MB of shared L3 cache.

Q: What is the release date gap between them?

A: The Xeon E5520 was released in March 2009, while the Core i3-5020U was released in February 2015, a gap of almost six years.

Specification Differences

| Specification | Intel Core i3-5020U | Intel Xeon E5520 |

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

| Cores | 2 | 4 |

| Threads | 4 | 8 |

| Base Clock | 2.20 GHz | 2.27 GHz |

| Boost Clock | None | 2.53 GHz |

| TDP | 15 W | 80 W |

| Socket | Intel BGA 1168 | Intel Socket 1366 |

| Architecture | Broadwell | Nehalem |

| Codename | Broadwell-U | Gainestown |

| Process Node | 14 nm | 45 nm |

| Transistors | 1,300 million | 731 million |

| Die Size | 82 mm² | 263 mm² |

| L3 Cache | 3 MB (shared) | 8 MB (shared) |

| Memory Bus | Dual-channel | Triple-channel |

| Memory Bandwidth | 25.6 GB/s | Not recorded |

| ECC Memory | No | Yes |

| Integrated Graphics | Intel HD 5500 | None |

| Market Segment | Mobile | Server/Workstation |

| Release Date | 2015-02-28 | 2009-03-29 |

| Launch MSRP | $281 | Not recorded |

The Verdict

The data points to a clear split by workload. For single-threaded tasks, the Xeon E5520 is the better performer. Its single-core Cinebench R23 score of 304 beats the i3-5020U's 264 by 13.2%, and its Cinebench R20 single-core score of 127 beats 110 by 13.4%. The Xeon's boost clock of 2.53 GHz, which the i3 lacks entirely, gives it a sustained frequency advantage that shows up in these tests.

For multi-threaded workloads, the Xeon still wins, but the margin is narrower than its core count would suggest. The Xeon scores 2155 in Cinebench R23 multi-core versus 1876 for the i3, a 12.9% gap. In Cinebench R15 multi-core, the Xeon scores 217 versus 188, a 13.4% gap. Doubling the cores and threads should theoretically double the multi-threaded throughput, but the i3's newer architecture and higher efficiency per clock keep the gap at roughly 13% rather than 50% or more.

The i3-5020U is not without merits. Its 15 W TDP is dramatically lower than the Xeon's 80 W, making it suitable for thin-and-light laptops where power draw and heat dissipation are primary constraints. Its integrated HD 5500 graphics remove the need for a discrete GPU, and its dual-channel memory with 25.6 GB/s of bandwidth is adequate for typical mobile use. The 14 nm process allows it to deliver comparable average benchmark scores, 757 versus 742, despite having half the cores.

The Xeon E5520, however, is the stronger choice for any compute-heavy scenario. Its 8 MB L3 cache, triple-channel memory, and ECC support make it a more capable platform for server or workstation duties. Its higher TDP is a non-issue in a desktop or rack environment where cooling is plentiful. The Xeon's 80 W envelope is a trade-off, but the performance data justifies it.

Where Each One Wins

The Intel Core i3-5020U wins in power efficiency and mobility. Its 15 W TDP is a fraction of the Xeon's 80 W, and its BGA 1168 socket is designed for permanent installation in laptops. The integrated HD 5500 graphics make it a complete solution for a portable system. It also has a much smaller die size, 82 mm² versus 263 mm², which reflects its modern manufacturing process. The i3's launch MSRP of $281 is recorded in the database, though the Xeon's launch price is not, making direct cost comparison impossible from the available data.

The Intel Xeon E5520 wins in raw performance and server features. It beats the i3 in every recorded benchmark, with consistent 13% leads across both single-core and multi-core tests. Its 8 MB L3 cache, triple-channel memory bus, and ECC support are advantages that matter in workstation and server environments. The Xeon's Socket 1366 platform allows for a replaceable CPU, unlike the soldered i3. Its 4 cores and 8 threads provide more parallel processing capacity, and its boost clock of 2.53 GHz gives it a higher peak frequency than the i3's fixed 2.20 GHz.

The overall average benchmark scores are nearly identical, 757 for the i3 versus 742 for the Xeon, and both sit at the 20th percentile among all CPUs. The nearest rivals for each part, the Xeon E5450 for the i3 and the Phenom II X4 B97 for the Xeon, also score within 0.3% of each other. This places both processors in the same performance tier. The Xeon's benchmark wins, however, are consistent and measurable, making it the superior choice for anyone who prioritizes compute throughput over power draw. The i3 is the better fit for a mobile device where battery life and low heat matter more than raw scores.