AMD Opteron 6276 vs Intel Xeon E3-1268L v5 Comparison

The AMD Opteron 6276 and Intel Xeon E3-1268L v5 present a fascinating comparison, as benchmark results show them to be nearly inseparable in performance despite radically different underlying designs. The Opteron, a 16-core Bulldozer-era server part from 2011, and the Xeon, a 4-core Skylake part from 2015, both achieve an average benchmark score of approximately 1560, placing them at the 39th percentile of all CPUs. The data reveals that architectural efficiency and core count can perfectly offset each other, resulting in a statistical dead heat across every single test.

FAQ

Q: Which processor has more cores?

A: The AMD Opteron 6276 has 16 cores and 16 threads, while the Intel Xeon E3-1268L v5 has 4 cores and 8 threads. This gives the AMD part a 4x advantage in physical core count.

Q: How do their average benchmark scores compare?

A: The AMD Opteron 6276 has an average benchmark score of 1560, while the Intel Xeon E3-1268L v5 scores 1557. The Opteron's nearest rival list shows a deltaPct of 0.2% versus the Xeon, indicating a negligible difference.

Q: What is the single-core performance difference?

A: In Cinebench R23 single-core, the Opteron scores 761 and the Xeon scores 760, a deltaPct of 0.1%. In both R15 and R20 single-core tests, both processors score identically at 76 and 319 respectively, with a deltaPct of 0%.

Q: Which processor has a lower TDP?

A: The Intel Xeon E3-1268L v5 has a TDP of 35 watts, while the AMD Opteron 6276 has a TDP of 115 watts. The Xeon consumes significantly less power per the specification data.

Q: What memory types do they support?

A: The AMD Opteron 6276 supports only DDR3 memory via a quad-channel bus with 51.2 GB/s bandwidth. The Intel Xeon E3-1268L v5 supports both DDR3 and DDR4 memory, but only through a dual-channel bus with 34.1 GB/s bandwidth.

Q: Which processor has integrated graphics?

A: Only the Intel Xeon E3-1268L v5 includes integrated graphics, specifically the HD Graphics P530. The AMD Opteron 6276 has no integrated graphics listed.

Architecture Differences

The architectural gap between these two processors is substantial, stemming from different design philosophies and manufacturing eras. The AMD Opteron 6276, built on the Bulldozer architecture with the codename Interlagos, uses a 32 nm process from GlobalFoundries. It packs 2,400 million transistors across a large die size of 2x 315 mm². The design prioritizes raw core count, featuring 16 cores and 16 threads, but organizes them in a modular fashion with 2 MB of L2 cache per module and 8 MB of L3 cache per die. This results in a total of 768 KB of L1 cache.

In contrast, the Intel Xeon E3-1268L v5 utilizes the Skylake architecture (codename Skylake-DT) on a much more advanced 14 nm process from Intel. It contains 1,750 million transistors on a single 122 mm² die, which is significantly smaller than the AMD's dual-die setup. The Intel design focuses on per-core efficiency, with 64 KB of L1 cache per core, 256 KB of L2 cache per core, and 8 MB of shared L3 cache. The Intel part also features a more modern PCIe Gen 3 interface with 16 lanes for the CPU, whereas the AMD Opteron is limited to PCIe Gen 2.

The difference in cache organization is particularly telling. The AMD's cache is allocated per module and per die, reflecting its multi-die, many-core design. The Intel's cache is per-core for L1 and L2, with a shared pool for L3, which is typical of a monolithic, high-frequency design. Additionally, the Intel Xeon includes integrated HD Graphics P530, a feature entirely absent from the AMD server chip. The Intel part also supports both DDR3 and DDR4 memory, while the AMD is restricted to DDR3 only.

Head-to-Head Benchmarks

The head-to-head benchmark data shows an extraordinary level of parity between the two processors. Across all six Cinebench tests, the AMD Opteron 6276 is declared the winner, but the margins are incredibly thin. In the Cinebench R15 multicore test, the Opteron scores 543 against the Xeon's 542, a deltaPct of just 0.2%. The single-core R15 test is a dead tie at 76 points for both.

Moving to Cinebench R20, the pattern continues. The Opteron wins the multicore test with 2265 points versus 2260 for the Xeon, again a 0.2% delta. The single-core scores are identical at 319 points each. The most recent Cinebench R23 results follow the same trend: the Opteron scores 5395 in multicore, edging out the Xeon's 5383 by 0.2%, and 761 in single-core versus 760, a 0.1% delta.

The data shows that the 16-core AMD processor manages to eke out a win in every benchmark, but the performance difference is so small as to be practically negligible. The Intel Xeon, with only a quarter of the cores, matches the AMD part almost exactly, demonstrating the massive generational improvement in Intel's per-core performance. The Opteron's advantage in multicore tests, while consistent, never exceeds a 0.2% deltaPct, meaning that in real-world usage, the two processors would perform identically in most workloads.

Specification Differences

The specification sheets for these two processors highlight their contrasting design targets. The most obvious difference is core and thread count: the AMD Opteron 6276 offers 16 cores and 16 threads, while the Intel Xeon E3-1268L v5 offers 4 cores and 8 threads. Clock speeds are also different, with the AMD base clock at 2.30 GHz and boost at 3.20 GHz, versus the Intel base clock at 2.40 GHz and boost at 3.40 GHz.

Power consumption presents a stark contrast, with the AMD TDP at 115 watts versus the Intel TDP at just 35 watts. The sockets are incompatible, as the AMD uses AMD Socket G34 while the Intel uses Intel Socket 1151. Manufacturing process and die size also differ greatly: the AMD is 32 nm with a 2x 315 mm² die, while the Intel is 14 nm with a 122 mm² die.

Memory specifications diverge significantly. The AMD supports only DDR3 with a quad-channel bus and 51.2 GB/s bandwidth, while the Intel supports DDR3 and DDR4 with a dual-channel bus and 34.1 GB/s bandwidth. PCIe support differs as well, with the AMD limited to Gen 2 and the Intel offering Gen 3 with 16 lanes. The Intel also includes integrated graphics, a feature the AMD lacks. The release dates are separated by four years, with the AMD launching on 2011-11-13 and the Intel on 2015-10-18.

The Verdict

The benchmark data presents an unusual situation where the choice between these two processors is not determined by performance, as they are statistically equivalent. The AMD Opteron 6276 wins all six head-to-head benchmarks, but the largest margin of victory is a mere 0.2% deltaPct. For multi-threaded workloads, the data shows the Opteron holds a consistent, though tiny, lead. However, the Intel Xeon E3-1268L v5 achieves this same level of performance with only 4 cores and 8 threads, compared to the Opteron's 16 cores and 16 threads.

From a technical specification standpoint, the Intel part is clearly more advanced, featuring a smaller 14 nm process, a much lower TDP of 35 watts versus 115 watts, and support for newer technologies like DDR4 memory and PCIe Gen 3. The AMD part is from an older generation, uses the larger 32 nm process, and is limited to DDR3 and PCIe Gen 2. Despite these architectural differences, the actual performance in Cinebench tests is virtually identical.

The choice comes down to platform preferences and feature requirements. If the workload demands maximum memory bandwidth, the AMD's quad-channel setup with 51.2 GB/s is superior. If lower power consumption and integrated graphics are priorities, the Intel is the only option. The data does not support a clear performance winner, so the decision must be made on other factors like memory support, PCIe generation, and the physical socket required.

Where Each One Wins

The AMD Opteron 6276 wins in all benchmark categories, but its victories are marginal. Its most significant advantage is in multicore performance, where it consistently scores slightly higher in every Cinebench iteration, from the R15 multicore test (543 vs 542) to the R23 multicore test (5395 vs 5383). The data also shows a theoretical advantage in memory bandwidth, as the AMD's quad-channel bus provides 51.2 GB/s compared to the Intel's dual-channel 34.1 GB/s. The AMD also has far more physical cores, which could be beneficial in heavily parallel workloads that scale beyond what the benchmarks show.

The Intel Xeon E3-1268L v5 wins in efficiency and platform modernity. Its TDP of 35 watts is less than a third of the AMD's 115 watts, making it a superior choice for power-constrained environments. The Intel supports both DDR3 and DDR4 memory, offering more flexibility in system configuration. It also features PCIe Gen 3, which provides double the bandwidth of the AMD's Gen 2 interface. The integrated HD Graphics P530 is a significant advantage for systems that require a display output without a discrete GPU. While it loses every benchmark by a tiny fraction, the Intel part achieves the same overall performance level with a fraction of the cores and power draw, indicating a much higher efficiency per watt in the data.