Intel Xeon E5-1660 v4 vs Intel Xeon E5-2676 v3 Comparison

Head-to-Head Benchmarks

The recorded data shows a clean sweep for the Intel Xeon E5-1660 v4 across all six Cinebench tests, though the margins are remarkably consistent rather than dramatic. In Cinebench R15 multi-core, the E5-1660 v4 scores 1137 against 1102 for the E5-2676 v3, a 3.2% advantage. The single-core R15 result follows the same pattern: 160 versus 155, again 3.2% ahead.

Moving to Cinebench R20, the multi-core test shows 4739 for the E5-1660 v4 and 4592 for the E5-2676 v3. The delta remains exactly 3.2%. Single-core R20 sees 669 versus 648, with the same 3.2% gap. The pattern holds through Cinebench R23: multi-core scores are 11285 and 10935, while single-core scores are 1593 and 1543. Every test, every generation of the benchmark, produces the identical 3.2% margin. This consistency is notable because it suggests the performance difference is structural, not workload-specific.

The aggregate benchmark data reinforces this picture. The E5-1660 v4 averages 3264 across all recorded benchmarks, placing it in the 53rd percentile of all CPUs. The E5-2676 v3 averages 3163, also in the 53rd percentile. The 101-point average gap (about 3.2%) lands both processors in the same performance tier, but the E5-1660 v4 consistently finishes ahead. In the nearest rival comparisons, the E5-1660 v4 sits within 0.4% of the Intel Xeon E5-1680 v3, AMD Ryzen Embedded V2516, Intel Core i3-12100T, and Intel Xeon E-2374G. The E5-2676 v3, meanwhile, tracks within 0.3% of the AMD Ryzen 5 5560U, AMD Ryzen 3 5300GE, AMD Ryzen 7 PRO 5850U, and Intel Xeon E5-2650 v4.

The benchmark sweep is unusual. Typically, a processor with more cores wins multi-threaded tests while losing single-threaded ones. Here, the E5-1660 v4 wins both categories despite having fewer cores. The explanation lies in clock speed and architecture efficiency, which the next section examines.

Architecture Differences

The two processors come from different Intel microarchitecture generations. The E5-1660 v4 uses Broadwell-EP, built on a 14 nm process node. The E5-2676 v3 uses Haswell-EP, built on a 22 nm process node. This node difference is significant: the 14 nm process allows for a smaller die (246 mm² versus 356 mm²) while packing more transistors (3,400 million versus 2,600 million). The E5-1660 v4 achieves higher density on a smaller physical footprint, which contributes to its clock speed advantage.

Core counts differ substantially. The E5-1660 v4 has 8 cores and 16 threads, while the E5-2676 v3 has 12 cores and 24 threads. The E5-2676 v3 brings 50% more cores to the table, yet it cannot translate that into a multi-core victory. The reason is clock speed. The E5-1660 v4 runs at a 3.20 GHz base clock and boosts to 3.80 GHz. The E5-2676 v3 runs at a 2.40 GHz base clock and boosts to 3.00 GHz. That is a 0.80 GHz base clock deficit and a 0.80 GHz boost clock deficit for the E5-2676 v3. In single-threaded work, the E5-1660 v4's higher clocks dominate. In multi-threaded work, the extra four cores of the E5-2676 v3 are not enough to overcome the per-core speed disadvantage.

Cache configurations also differ. The E5-1660 v4 has 20 MB of shared L3 cache, while the E5-2676 v3 has 30 MB of shared L3 cache. The L1 and L2 caches are identical in size per core (64 KB and 256 KB respectively). The larger L3 on the E5-2676 v3 likely helps with its 12-core workload distribution, but the benchmark data shows it does not compensate for the clock deficit.

Memory support differs in an important way. The E5-1660 v4 supports DDR4 memory only, with a quad-channel bus delivering 76.8 GB/s of bandwidth. The E5-2676 v3 supports both DDR3 and DDR4, also on a quad-channel bus, but its bandwidth is lower at 68.3 GB/s. The E5-1660 v4's exclusive DDR4 support and higher bandwidth give it an edge in memory-intensive workloads, though the head-to-head test results show the same 3.2% margin across all tests, implying the memory difference is not creating additional separation beyond the clock speed effect.

Both processors share several traits: Intel Socket 2011-3, PCIe Gen 3 with 40 lanes (CPU only), ECC memory support, no integrated graphics, and a locked multiplier. Both are end-of-life products. The E5-1660 v4 is classified as a Desktop segment part with a launch MSRP of $1113, while the E5-2676 v3 is classified as Server/Workstation with no recorded launch MSRP. The E5-1660 v4 carries part number SR2PK and was released in June 2016; the E5-2676 v3 carries part number SR1Y5 with no release date recorded.

The power draw tells an interesting story. The E5-1660 v4 has a TDP of 140 watts, while the E5-2676 v3 has a TDP of 120 watts. The E5-1660 v4 draws more power despite having fewer cores and a smaller die. This is the cost of its higher clock speeds. The E5-2676 v3, with its 12 cores and lower clocks, spreads its power budget across more cores at a slower pace.

FAQ

Q: Which processor wins in multi-core workloads?

A: The Intel Xeon E5-1660 v4 wins all three multi-core Cinebench tests (R15, R20, R23) with a 3.2% margin over the E5-2676 v3, despite having only 8 cores versus 12 cores.

Q: How do the single-core scores compare?

A: The E5-1660 v4 leads in every single-core test by 3.2%. In Cinebench R15, it scores 160 versus 155; in R20, 669 versus 648; in R23, 1593 versus 1543.

Q: What is the core and thread difference?

A: The E5-1660 v4 has 8 cores and 16 threads. The E5-2676 v3 has 12 cores and 24 threads. The E5-2676 v3 has 50% more cores but cannot convert that into a benchmark win.

Q: Which processor has more cache?

A: The E5-2676 v3 has 30 MB of shared L3 cache, while the E5-1660 v4 has 20 MB. Both have identical 64 KB L1 and 256 KB L2 caches per core.

Q: Do both processors support ECC memory?

A: Yes, both support ECC memory. The E5-1660 v4 supports DDR4 only with 76.8 GB/s bandwidth. The E5-2676 v3 supports both DDR3 and DDR4 with 68.3 GB/s bandwidth.

Q: What are the power requirements?

A: The E5-1660 v4 has a 140 watt TDP. The E5-2676 v3 has a 120 watt TDP. The E5-1660 v4 consumes more power despite having fewer cores, due to its higher clock speeds.

Specification Differences

| Specification | Intel Xeon E5-1660 v4 | Intel Xeon E5-2676 v3 |

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

| Cores | 8 | 12 |

| Threads | 16 | 24 |

| Base Clock | 3.20 GHz | 2.40 GHz |

| Boost Clock | 3.80 GHz | 3.00 GHz |

| TDP | 140 W | 120 W |

| Architecture | Broadwell | Haswell |

| Codename | Broadwell-EP | Haswell-EP |

| Process Node | 14 nm | 22 nm |

| Transistors | 3,400 million | 2,600 million |

| Die Size | 246 mm² | 356 mm² |

| L3 Cache | 20 MB (shared) | 30 MB (shared) |

| Memory Support | DDR4 | DDR3, DDR4 |

| Memory Bandwidth | 76.8 GB/s | 68.3 GB/s |

| Market Segment | Desktop | Server/Workstation |

| Release Date | 2016-06-19 | Not recorded |

| Launch MSRP | $1113 | Not recorded |

| Part Number | SR2PK | SR1Y5 |

The Verdict

The data supports a clear but nuanced conclusion. The Intel Xeon E5-1660 v4 is the faster processor in every recorded benchmark, winning all six head-to-head tests by a uniform 3.2%. It achieves this with fewer cores, relying on higher base and boost clocks (3.20/3.80 GHz versus 2.40/3.00 GHz) and a more advanced 14 nm process node. Its average benchmark score of 3264 versus 3163 for the E5-2676 v3 confirms the overall advantage.

The E5-2676 v3 is not without merit. It offers 12 cores and 24 threads, 30 MB of L3 cache, dual memory support (DDR3 and DDR4), and a lower TDP of 120 watts. For workloads that scale linearly with core count and do not heavily depend on clock speed, the E5-2676 v3 could theoretically hold its own. However, the recorded Cinebench results show no such workload: the E5-1660 v4 wins even in multi-core tests where the E5-2676 v3's extra cores should help.

Users who prioritize raw benchmark performance should select the E5-1660 v4. Its consistent 3.2% lead across every test makes it the safer choice for single-threaded and multi-threaded applications alike. Users who require the higher core count for specific server or workstation workloads, or who need DDR3 compatibility for existing memory infrastructure, may find the E5-2676 v3 suitable. The E5-2676 v3 also draws 20 watts less power, which could matter in densely populated server environments.

The 53rd percentile ranking for both processors indicates they sit in the middle of the overall CPU performance distribution. Neither is a top-tier part by modern standards, but within this head-to-head pairing, the E5-1660 v4 is the outright winner in every recorded metric. The benchmark data is unambiguous: six wins for the E5-1660 v4, zero for the E5-2676 v3, and a consistent 3.2% margin throughout.