AMD EPYC 7251 vs Intel Xeon E5-2678 v3 Comparison

The Intel Xeon E5-2678 v3 and the AMD EPYC 7251 are both 120W server processors, but they represent fundamentally different design philosophies. The Xeon is a 12-core Haswell-EP part built on Intel's 22nm process, while the EPYC is an 8-core Zen part on GlobalFoundries' 14nm process. Benchmark data shows the EPYC 7251 consistently outperforms the Xeon across all Cinebench tests, despite having fewer cores, with a perfect 6-0 win record in head-to-head comparisons.

Head-to-Head Benchmarks

The AMD EPYC 7251 wins every single benchmark in the comparison, though the margins are remarkably consistent and narrow. In Cinebench R15 multicore, the EPYC scores 1279 against the Xeon's 1257, a 1.7% advantage. The single-core result in the same test shows the same pattern: 180 for AMD versus 177 for Intel, again a 1.7% delta. This consistency across both single and multi-threaded workloads is notable because it suggests the EPYC's advantage is architectural rather than core-count dependent.

Moving to Cinebench R20, the EPYC 7251 posts 5331 in multicore versus 5239 for the Xeon E5-2678 v3, and 752 versus 739 in single-core. The 1.7% delta persists across every test in the suite. The most demanding workload, Cinebench R23, shows the EPYC reaching 12694 multicore and 1792 single-core, while the Xeon manages 12474 and 1761 respectively.

The uniformity of the 1.7% delta across all six benchmarks is striking. It indicates a consistent performance advantage that scales from lightly threaded to heavily threaded workloads. The EPYC achieves this with 8 cores and 16 threads, while the Xeon has 12 cores and 24 threads. This means the AMD part's per-core efficiency is substantially higher - roughly 50% more cores on the Intel side only yields a 1.7% deficit, implying the Zen architecture delivers far more work per core clock.

In terms of average benchmark score, the EPYC 7251 sits at 3671, placing it in the 56th percentile of all CPUs. The Xeon E5-2678 v3 averages 3608, in the 55th percentile. The EPYC's nearest rivals include the AMD Ryzen 7 PRO 1700X at 3673 (0.1% ahead) and the Intel Core i3-13100E at 3668 (0.1% behind), while the Xeon sits near the AMD Ryzen 7 PRO 1700 at 3613 (0.1% ahead) and the Intel Xeon E-2286G at 3610 (0.1% ahead).

FAQ

Q: Which processor wins in single-core performance?

A: The AMD EPYC 7251 wins all three single-core tests. In Cinebench R15 it scores 180 versus 177, in R20 it scores 752 versus 739, and in R23 it scores 1792 versus 1761. Each margin is 1.7%.

Q: Does the Intel Xeon's higher core count help in multi-threaded workloads?

A: No. Despite having 12 cores and 24 threads versus the EPYC's 8 cores and 16 threads, the Xeon loses every multicore test. The EPYC wins by 1.7% in Cinebench R15, R20, and R23 multicore tests, scoring 1279, 5331, and 12694 respectively.

Q: What is the average benchmark score difference between these two CPUs?

A: The EPYC 7251 has an average benchmark score of 3671, while the Xeon E5-2678 v3 averages 3608. This puts the EPYC in the 56th percentile of all CPUs versus the Xeon's 55th percentile.

Q: How do these processors compare to their nearest rivals?

A: The EPYC 7251 is closely matched with the AMD Ryzen 7 PRO 1700X (3673, 0.1% ahead) and the Intel Core i3-13100E (3668, 0.1% behind). The Xeon E5-2678 v3 sits near the AMD Ryzen 7 PRO 1700 (3613, 0.1% ahead) and the AMD Ryzen 7 2700E (3603, 0.1% behind).

Q: Are there any benchmark categories where the Intel Xeon wins?

A: Based on the head-to-head benchmark data, the Xeon E5-2678 v3 does not win any of the six Cinebench tests. The EPYC 7251 wins all six, with winsA showing 0 and winsB showing 6.

Q: What is the production status of each processor?

A: The Intel Xeon E5-2678 v3 is listed as end-of-life, while the AMD EPYC 7251 is marked as active production. The EPYC was released on 2017-06-28.

Architecture Differences

The two processors embody different architectural generations. The Intel Xeon E5-2678 v3 uses the Haswell architecture, specifically Haswell-EP, built on Intel's 22nm process with a die size of 356 mm² and 2,600 million transistors. The AMD EPYC 7251 uses the Zen architecture with the Naples codename, fabricated by GlobalFoundries on a 14nm process with a smaller die of 213 mm² but a higher transistor count of 4,800 million.

Cache organization differs significantly. The Xeon provides 64 KB of L1 cache per core, 256 KB of L2 per core, and 30 MB of shared L3 cache. The EPYC offers larger per-core caches: 96 KB of L1 per core, 512 KB of L2 per core, and 32 MB of shared L3. This larger cache hierarchy on the EPYC likely contributes to its per-core efficiency advantage.

Memory architecture is another major divider. The Xeon supports both DDR3 and DDR4 memory with a quad-channel bus delivering 68.3 GB/s of bandwidth. The EPYC supports only DDR4 but uses an eight-channel configuration, doubling the theoretical memory bandwidth to 153.6 GB/s. Both support ECC memory.

PCIe capabilities differ in presentation: the Xeon specifies "Gen 3, 40 Lanes (CPU only)" while the EPYC simply lists "Gen 3" without lane count. The Xeon uses Intel Socket 2011-3, while the EPYC uses AMD Socket SP3. The EPYC has an unlocked multiplier, while the Xeon does not.

Specification Differences

The core and thread counts are the most visible difference: the Xeon E5-2678 v3 has 12 cores and 24 threads, while the EPYC 7251 has 8 cores and 16 threads. Clock speeds also favor the Intel part on paper, with a 2.50 GHz base and 3.30 GHz boost versus the EPYC's 2.10 GHz base and 2.90 GHz boost.

Both processors share a 120W TDP, but their process technologies differ: 22nm for Intel versus 14nm for AMD. The transistor counts and die sizes diverge substantially, with the EPYC packing more transistors (4,800 million) into a smaller die (213 mm²) compared to the Xeon's 2,600 million transistors on a 356 mm² die.

Memory support is a key differentiator: the Xeon supports DDR3 and DDR4 with quad-channel access and 68.3 GB/s bandwidth, while the EPYC supports only DDR4 but with eight-channel access and 153.6 GB/s bandwidth. Both support ECC memory.

Socket compatibility is entirely different, with the Xeon using Intel Socket 2011-3 and the EPYC using AMD Socket SP3. The EPYC has an unlocked multiplier; the Xeon does not. The part numbers also differ: SR20Z for the Xeon, and PS7251BFV8SAFPS7251BFAFWOF for the EPYC.

The EPYC has a recorded release date of 2017-06-28 and its production status is active, while the Xeon is end-of-life. The EPYC belongs to the EPYC 7001 series, while the Xeon has no series designation.

Where Each One Wins

The AMD EPYC 7251 wins in every measured benchmark category. Its six head-to-head victories span both single-core and multi-core tests across three Cinebench versions. The consistent 1.7% margin suggests the EPYC's architectural efficiency, with larger per-core caches and higher memory bandwidth, provides a universal advantage regardless of workload characteristics.

The EPYC's 153.6 GB/s memory bandwidth versus the Xeon's 68.3 GB/s indicates a major advantage for memory-intensive workloads, even though the benchmark data does not directly measure memory-bound scenarios. The eight-channel memory architecture and larger L3 cache (32 MB versus 30 MB) position the EPYC favorably for virtualized environments or database workloads where memory throughput is critical.

The Intel Xeon E5-2678 v3 does not win any benchmark in the data set, but its specification sheet suggests potential advantages in specific deployment scenarios. Its 12 cores and 24 threads provide more parallel hardware threads, which could benefit workloads that scale imperfectly with core efficiency. The dual memory support (DDR3 and DDR4) offers flexibility for legacy infrastructure, and the higher boost clock of 3.30 GHz versus 2.90 GHz could help lightly threaded latency-sensitive tasks, though the benchmark data does not confirm this advantage.

The production status difference matters for procurement decisions: the Xeon is end-of-life, while the EPYC remains active. For new deployments, the EPYC's active status and superior benchmark results make it the clear choice. For existing infrastructure locked into the Intel Socket 2011-3 platform, the Xeon remains functional but offers no performance advantage over the EPYC in the tested workloads.