Intel Core i7-3820 vs Intel Xeon E3-1505L v5 Comparison

The Intel Xeon E3-1505L v5 and the Intel Core i7-3820 are both 4-core, 8-thread processors, but they come from very different eras and design philosophies. The database results show that while the newer Xeon wins every single benchmark, the margin is consistently narrow, making this a closer contest than the generational gap might suggest. This analysis breaks down the recorded data to see where each chip stands.

Head-to-Head Benchmarks

Across the six recorded Cinebench tests, the Intel Xeon E3-1505L v5 dominates the Intel Core i7-3820 in every instance. The victories are consistent, but the margins are slim, ranging from 1.4% to 2.9%. This indicates that while the Xeon has a technical edge, the older Core i7 remains surprisingly competitive in raw compute throughput.

In the multicore tests, the Xeon scores 503 points in Cinebench R15 versus 496 for the Core i7, a 1.4% lead. This pattern repeats in Cinebench R20, where the Xeon posts 2099 points against the Core i7's 2067, a 1.5% advantage. The largest multicore gap appears in Cinebench R23, where the Xeon scores 4999 points compared to 4923 for the Core i7, again a 1.5% difference. The data suggests that in heavily threaded workloads, the newer architecture of the Xeon provides a slight but measurable edge.

The single-core results tell a similar story with slightly wider margins. In Cinebench R15 single-core, the Xeon scores 71 points against the Core i7's 69, a 2.9% lead, which is the largest delta in the entire benchmark set. Cinebench R20 shows the Xeon at 296 points versus 291 for the Core i7, a 1.7% advantage. Finally, Cinebench R23 single-core sees the Xeon score 705 points against 695, a 1.4% lead. These results indicate that the Xeon's architectural improvements translate into better per-thread performance, though the Core i7's high boost clock keeps it close.

The average benchmark score further illustrates the parity. The Xeon E3-1505L v5 has an average score of 1446, while the Core i7-3820 sits at 1424. Interestingly, the Xeon's percentile ranking is 38, which is just one point higher than the Core i7's percentile of 37. Both chips sit in the lower-middle tier of all CPUs in the database, with the Xeon's nearest rivals including the AMD Opteron 6378 (1447, -0.1%) and the Intel Core i5-7300HQ (1448, -0.1%). The Core i7's nearest rivals include the Intel Xeon Bronze 3106 (1422, 0.1%) and the Intel Core i5-4570S (1426, -0.2%). These figures confirm that the two processors perform in a similar bracket, with the Xeon's wins being consistent but not decisive.

Architecture Differences

The foundational difference between these two CPUs is their process node and architecture generation. The Xeon E3-1505L v5 is built on Intel's 14 nm process using the Skylake-H architecture, while the Core i7-3820 uses the older 32 nm process with the Sandy Bridge-E architecture. This is a two-generation leap in manufacturing technology, which explains the Xeon's lower power draw and smaller die size.

The die size difference is substantial: the Xeon measures 122 mm² with 2,300 million transistors, while the Core i7 has a much larger 294 mm² die with 1,270 million transistors. The smaller process node allows the Xeon to pack nearly twice as many transistors into less than half the physical space. This density advantage is a key reason why the Xeon can operate at a much lower thermal design power (TDP).

Cache configurations also differ. Both chips have 64 KB of L1 cache and 256 KB of L2 cache per core, but the shared L3 cache is larger on the Core i7, with 10 MB versus the Xeon's 8 MB. Despite having less L3 cache, the Xeon's newer architecture and memory controller design compensate, as shown by its benchmark wins.

Memory support is another significant divergence. The Xeon supports both DDR3 and DDR4 memory across a dual-channel bus, providing 34.1 GB/s of bandwidth. The Core i7 supports only DDR3, but it does so on a quad-channel bus, delivering 51.2 GB/s of bandwidth. This gives the Core i7 a theoretical memory bandwidth advantage of 50%, which is notable for memory-sensitive workloads, though it does not translate into benchmark wins in the recorded data.

The integrated graphics situation is also different. The Xeon includes an HD Graphics P530 iGPU, while the Core i7 has no integrated graphics at all. This makes the Xeon a more flexible option for systems that require a display output without a discrete GPU. Additionally, the Xeon supports ECC memory, a feature absent on the Core i7, which is critical for workstation and server reliability.

Platform connectivity differs as well. The Xeon uses an Intel BGA 1440 socket with 16 PCIe Gen 3 lanes, while the Core i7 uses an Intel Socket 2011 with 40 PCIe Gen 2 lanes. The Core i7 offers more lanes, but they are an older generation, whereas the Xeon has fewer but faster lanes. The Core i7 is also multiplier-unlocked, allowing for overclocking, while the Xeon is locked.

FAQ

Q: Which processor has a higher TDP?

A: The Intel Core i7-3820 has a TDP of 130 watts, which is significantly higher than the Intel Xeon E3-1505L v5's 25 watts. This makes the Xeon far more power-efficient.

Q: Does the Core i7-3820 support ECC memory?

A: No, ECC memory support is exclusive to the Xeon E3-1505L v5. The Core i7-3820 does not support ECC, which is a key differentiator for workstation reliability.

Q: What is the largest performance delta between the two chips in the recorded benchmarks?

A: The largest performance delta is in the Cinebench R15 single-core test, where the Xeon E3-1505L v5 leads by 2.9%, scoring 71 points versus 69 points for the Core i7-3820.

Q: Which processor has more PCIe lanes?

A: The Core i7-3820 has 40 PCIe Gen 2 lanes, while the Xeon E3-1505L v5 has 16 PCIe Gen 3 lanes. The Core i7 offers more lanes, but they are from an older generation.

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

A: Yes, both the Xeon E3-1505L v5 and the Core i7-3820 have 4 cores and 8 threads. They also share identical L1 and L2 cache sizes per core.

Q: Which chip has a higher boost clock?

A: The Core i7-3820 has a higher boost clock at 3.80 GHz, compared to the Xeon E3-1505L v5's 2.80 GHz. Despite this, the Xeon wins all single-core benchmark tests.

Specification Differences

| Specification | Intel Xeon E3-1505L v5 | Intel Core i7-3820 |

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

| Base Clock | 2.00 GHz | 3.60 GHz |

| Boost Clock | 2.80 GHz | 3.80 GHz |

| TDP | 25 W | 130 W |

| Socket | Intel BGA 1440 | Intel Socket 2011 |

| Architecture | Skylake | Sandy Bridge |

| Process Node | 14 nm | 32 nm |

| Transistors | 2,300 million | 1,270 million |

| Die Size | 122 mm² | 294 mm² |

| L3 Cache | 8 MB (shared) | 10 MB (shared) |

| Memory Support | DDR3, DDR4 | DDR3 |

| Memory Bus | Dual-channel | Quad-channel |

| Memory Bandwidth | 34.1 GB/s | 51.2 GB/s |

| ECC Memory | Yes | No |

| PCIe | Gen 3, 16 Lanes | Gen 2, 40 Lanes |

| Integrated Graphics | HD Graphics P530 | None |

| Market Segment | Server/Workstation | Desktop |

| Release Date | 2015-10-26 | 2012-02-12 |

| Launch MSRP | $433 | $305 |

| Multiplier Unlocked | No | Yes |

The Verdict

The data points to the Intel Xeon E3-1505L v5 as the overall winner, taking all six head-to-head benchmarks and holding a higher average score of 1446 versus 1424. The Xeon also offers substantial platform advantages, including ECC memory support, integrated graphics, a modern 14 nm process, and a dramatically lower TDP of 25 watts compared to the Core i7's 130 watts. For any scenario where power efficiency, reliability, or a compact platform is a priority, the Xeon is the clear choice.

However, the Core i7-3820 is not to be dismissed. Its 40 PCIe lanes and quad-channel memory bus provide 51.2 GB/s of bandwidth, which is 50% higher than the Xeon's 34.1 GB/s. This makes it a compelling option for workloads that are heavily dependent on memory throughput or require extensive expansion capabilities. Its unlocked multiplier also allows for manual overclocking, which can offset its architectural disadvantage in sustained workloads. The Core i7's lower launch MSRP of $305 also reflects its different positioning, though price is not a factor in performance analysis.

The benchmark deltas are so small, ranging from 1.4% to 2.9%, that real-world differences will be minimal in most applications. The Xeon wins on efficiency and modern features, while the Core i7 wins on raw platform bandwidth and overclocking headroom.

Where Each One Wins

The Intel Xeon E3-1505L v5 is the better choice for compact, power-constrained systems. Its 25-watt TDP makes it suitable for small form factor workstations or embedded server applications where heat and power draw are critical. The inclusion of ECC memory support and an integrated GPU makes it a dependable option for a silent, low-power workstation that needs to handle error-corrected memory and provide a display output without a discrete card. Its consistent wins in all Cinebench tests, including a 1.5% lead in Cinebench R23 multicore, show that it delivers modern performance efficiency.

The Intel Core i7-3820 wins in scenarios that demand high memory bandwidth and extensive PCIe expansion. The quad-channel memory bus provides 51.2 GB/s of bandwidth, which is a 50% advantage over the Xeon. This is a measurable benefit for data-heavy tasks like large database operations or certain scientific computing workloads that saturate memory channels. The 40 PCIe Gen 2 lanes allow for a greater number of expansion cards, such as multiple GPUs or specialized controllers. Its unlocked multiplier also gives enthusiasts the ability to push the 3.80 GHz boost clock higher, potentially closing the small performance gap seen in the benchmarks.