Xeon E5-2666 v3

Details and Benchmarks for Intel Xeon E5-2666 v3

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Benchmark Results

Combined benchmark scores based on multiple data points, giving a quick overview of this processor's performance.

Overall Score

Overall score for Xeon E5-2666 v3 based on all benchmark results gathered. Look at this like a meta score, you will find more specific workload ratings below.

5,166 Rank: 734
Rank Name Score Visual
730 Xeon E3-1220 v5 5,171
+0.1%
731 Core i7 X 000 5,168
+0%
732 Core i3-1115G4 5,167
+0%
733 Core i5-6500 5,166
+0%
734 Xeon E5-2666 v3 5,166
735 FX-8100 5,164
+-0%
736 Ryzen 5 4600HS 5,164
+-0%
737 Ryzen 3 2200G 5,162
-0.1%
738 Xeon E5-2687W v2 5,158
-0.2%
739 Xeon E5-2630 v3 5,157
-0.2%

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Multicore Score

Multicore performance score for Xeon E5-2666 v3 based on multi-threaded benchmark results.

5,000 Rank: 642
Rank Name Score Visual
638 Xeon E-2136 5,008
+0.2%
639 Core i5-10500 5,008
+0.2%
640 Ryzen 3 3300X 5,004
+0.1%
641 Xeon E-2176M 5,000
+0%
642 Xeon E5-2666 v3 5,000
643 Core i5-1038NG7 4,999
+-0%
644 Xeon E3-1280 v5 4,998
+-0%
645 Ryzen 3 5425U 4,997
-0.1%
646 Xeon E3-1231 v3 4,996
-0.1%
647 Core i3-10300 4,996
-0.1%

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Singlecore Score

Single-core performance score for Xeon E5-2666 v3 based on single-threaded benchmark results.

5,277 Rank: 747
Rank Name Score Visual
743 Core i3-4350 5,282
+0.1%
744 Core i7-6820HQ 5,279
+0%
745 Xeon E3-1230 V2 5,279
+0%
746 Ryzen 5 PRO 3400G 5,278
+0%
747 Xeon E5-2666 v3 5,277
748 Xeon E3-1505M v5 5,276
+-0%
749 Core i5-7500T 5,274
-0.1%
750 Xeon E3-1240L v5 5,273
-0.1%
751 Core i7-4960X 5,271
-0.1%
752 Pentium Gold G4620 5,270
-0.1%

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Workload Scores

Performance scores grouped by workload type, normalized and aggregated from multiple raw benchmark results.

Number Crunching

Aggregated score for Xeon E5-2666 v3 based on integer math, floating point math, and prime number computation benchmarks.

4,971 Rank: 402
Rank Name Score Visual
398 Ryzen 7 2700X 4,980
+0.2%
399 Xeon E5-2667 v4 4,977
+0.1%
400 Xeon E5-2650 v4 4,977
+0.1%
401 Core i9-10980HK 4,972
+0%
402 Xeon E5-2666 v3 4,971
403 Xeon E-2286M 4,970
+-0%
404 Xeon E5-2648L v4 4,969
+-0%
405 Xeon E5-2670 v3 4,967
-0.1%
406 Ryzen 7 PRO 2700X 4,961
-0.2%
407 Ryzen Threadripper 1900X 4,960
-0.2%

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Data Processing

Aggregated score for Xeon E5-2666 v3 based on data encryption, data compression, and string sorting benchmarks.

5,048 Rank: 398
Rank Name Score Visual
394 Xeon w3-2425 5,059
+0.2%
395 Xeon E5-2695 v2 5,055
+0.1%
396 Core Ultra 7 258V 5,051
+0.1%
397 Ryzen 5 4600H 5,048
+0%
398 Xeon E5-2666 v3 5,048
399 Xeon Gold 5215 5,047
+-0%
400 Ryzen 5 PRO 2600 5,047
+-0%
401 Xeon Silver 4116T 5,045
-0.1%
402 Ryzen 5 4600HS 5,044
-0.1%
403 Xeon Gold 6134 5,043
-0.1%

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Physics & Compute

Aggregated score for Xeon E5-2666 v3 based on physics simulation and extended instruction set (SSE/AVX) benchmarks.

4,985 Rank: 400
Rank Name Score Visual
396 Core i5-10600K 4,987
+0%
397 Core i7-9700E 4,987
+0%
398 Ryzen 5 3500 4,986
+0%
399 Xeon E-2286M 4,985
+0%
400 Xeon E5-2666 v3 4,985
401 Xeon Silver 4114 4,980
-0.1%
402 Core i5-10600KF 4,980
-0.1%
403 Xeon Silver 4210 4,978
-0.1%
404 Xeon E5-2618L v4 4,978
-0.1%
405 Xeon E5-2670 v3 4,978
-0.1%

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Xeon E5-2666 v3 Details

Ranking #733 of 2060 in overall performance, the Intel Xeon E5-2666 v3 remains a notable server and workstation processor from the Haswell-EP generation, launched in November 2014. While now over a decade old, it continues to hold relevance in legacy systems and environments where multi-threaded workloads and ECC memory support are critical. Its performance today, as of March 2026, reflects its position as a mid-tier offering in the broader CPU landscape, particularly when compared to modern high-end processors, but it still delivers respectable throughput in multi-core tasks.

Built on Intel’s 22 nm process and based on the Haswell-EP architecture, the Xeon E5-2666 v3 features 10 cores and 20 threads thanks to Hyper-Threading. It operates at a base frequency of 2.9 GHz, with a turbo boost up to 3.5 GHz, and is designed for the Socket 2011-3 platform. The processor includes 25 MB of L3 cache, which is split across the cores to support high-bandwidth workloads, and it supports up to two-way symmetric multiprocessing (SMP), enabling dual-processor configurations for enhanced scalability. The chip consumes 135 W under full load, requiring robust cooling solutions, especially in densely packed server environments.

Memory support includes DDR3 and DDR4 at speeds up to 2133 MT/s via a quad-channel interface, with ECC memory compatibility ensuring data integrity—key for server and workstation applications. The CPU supports PCIe 3.0 with 40 lanes directly from the processor, providing ample bandwidth for high-speed storage and expansion cards. Despite lacking integrated graphics, the Xeon E5-2666 v3 is equipped with advanced virtualization technologies such as Intel VT-x, VT-d, and TXT, making it well-suited for virtualized environments and cloud infrastructure.

In benchmark testing, the Xeon E5-2666 v3 achieves a single-core score of 5277, placing it at #747 in single-threaded performance, and a multicore score of 5000, ranking #641 in multi-threaded performance. The overall score of 5166 positions it just above the Core i3-1115G4 and just below the Core i7 X 000, indicating that while it is no longer competitive with modern consumer CPUs, it still holds its own in multi-threaded workloads, particularly in systems where memory bandwidth and thread count are prioritized.

The processor supports a wide range of instruction sets, including AVX2, FMA3, and BMI1/2, enabling optimized performance in scientific computing, data processing, and virtualization. It also supports Intel’s vPro technology, enhancing manageability and security in enterprise deployments. While it lacks AVX-512, which is present in more recent Intel CPUs, its feature set remains robust for its era.

As of 2026, the Xeon E5-2666 v3 is best suited for legacy server environments, small-scale virtualization, and workstations requiring ECC memory and high core counts. It is not ideal for modern gaming or single-threaded applications but remains a viable option in cost-sensitive or long-term deployment scenarios where its multi-threaded performance and server-grade features are valued.
Frequently Compared

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Intel Atom Z530 34 views

AMD Ryzen 5 3600 33 views

AMD A10-7400P 33 views

Intel Core 2 Duo E8600 33 views

AMD Ryzen 3 PRO 2200GE 32 views

AMD Ryzen 5 3500X 32 views

Intel Atom Z520 32 views

Intel Xeon Silver 4214 31 views

Intel Xeon Silver 4110 30 views

Intel Xeon E5-2666 v3

Main Specifications

Designer: Intel
Name: Xeon E5-2666 v3
Cores: 10
Threads: 20
Base Frequency: 2900 MHz
Clock Multiplier: 29x (locked)
Core Name: Haswell-EP
Socket: Socket 2011-3
Package: FC-LGA12A
Target Segment: Workstation
TDP: 135 W

Cache Specifications

L1 Cache: 62.464 KiB
L2 Cache: 0.244 MiB
L3 Cache: 23.842 MiB

Memory Specifications

Supported Memory Type: DDR3, DDR42133 MHz Quad-channel

Physical Specifications

Process: 22 nm
Die Area: 356 mm²
Manufacturer: Intel

CPU Features

MMX SSE SSE2 SSE3 SSSE3 SSE4.2 AVX AVX2 BMI1 BMI2 FMA3 CLMUL F16C EIST TXT vPro VT-x VT-d TSX
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