Intel Core i7-3960X vs Intel Xeon E5-2628 v3 Comparison

Where Each One Wins

The benchmark data is unusually lopsided in this pairing. The Intel Xeon E5-2628 v3 wins all six recorded Cinebench comparisons, while the Intel Core i7-3960X does not win a single test in the head-to-head set. That said, the margins are so narrow that the practical difference in everyday use is negligible. The Xeon's largest advantage is a 0.1% lead in multi-core Cinebench R15, R20, and R23, which translates to a handful of points: 723 versus 722, 3015 versus 3011, and 7179 versus 7170 respectively. These deltas are within run-to-run noise for most workloads.

The single-core results are effectively ties. Both chips record 102 points in Cinebench R15 single-core, 425 points in R20 single-core, and the Xeon leads by one point in R23 single-core at 1013 versus 1012. If you prioritize single-threaded responsiveness, the data shows no meaningful winner here.

The Xeon's wins come from its core and thread advantage: 8 cores and 16 threads versus 6 cores and 12 threads. The Core i7-3960X counters with higher clock speeds: a 3.30 GHz base and 3.90 GHz boost against the Xeon's 2.50 GHz base and 3.00 GHz boost. Yet the benchmark results show the Xeon's extra cores outweigh the Core i7's frequency advantage in multi-threaded Cinebench loads. The Core i7 does have a Geekbench result in the database (3193 multi-core, 657 single-core), but no corresponding Geekbench score exists for the Xeon, so a direct comparison on that test is not possible from this data.

For server or workstation tasks that scale with core count, the Xeon is the safer pick. For desktop workloads where clock speed matters and you already own the older platform, the Core i7's higher boost clock keeps it competitive, but the recorded scores do not show it ahead anywhere.

The Verdict

Pick the Intel Xeon E5-2628 v3 if you need more parallel throughput, ECC memory support, or a newer platform with DDR4. The data shows it ahead in every recorded multi-core Cinebench test, and its 8-core/16-thread configuration gives it a structural advantage in heavily threaded rendering or virtualization workloads. The Xeon also supports ECC memory, which matters for long-running workstations or small servers where data integrity is critical. Its 85 W TDP is notably lower than the Core i7's 130 W, which simplifies cooling in dense chassis.

Pick the Intel Core i7-3960X if you are upgrading an existing Socket 2011 system and want higher clock speeds without changing platforms. Its 3.90 GHz boost clock is 0.90 GHz higher than the Xeon's, and its unlocked multiplier allows overclocking, which the Xeon does not offer. For single-threaded tasks, the recorded scores are identical or within one point, so the Core i7 does not lose anything meaningful on lightly threaded work. The Core i7 also has a Geekbench result (3193 multi-core, 657 single-core), making it the only one of the two with data for that test.

The database percentiles reflect the near-tie: the Xeon sits at the 46th percentile across all CPUs, while the Core i7 sits at the 45th. Their average benchmark scores are 2076 and 2037 respectively, a gap of about 1.9%. The nearest rivals confirm the tight grouping: the Xeon's closest competitor, the Intel Xeon W-2123, scores 2079 (0.1% higher), and the Core i7's closest rival, the AMD Opteron 6386 SE, scores 2038 (0% delta). Neither chip dominates its peer group by any meaningful margin.

If you are building fresh, the Xeon's platform advantages (DDR4, ECC, lower TDP) make it the more forward-looking choice. If you are refreshing an existing Sandy Bridge-E system, the Core i7's unlocked multiplier and higher clocks are the practical draw. The benchmark data alone does not justify replacing one with the other.

Head-to-Head Benchmarks

The largest multi-core win for the Xeon comes in Cinebench R23, where it scores 7179 against the Core i7's 7170, a 0.1% difference. The same pattern repeats in R15 (723 versus 722) and R20 (3015 versus 3011). These are the only three multi-core tests in the head-to-head set, and the Xeon wins each by exactly one to four points.

Single-core results are even closer. Cinebench R15 single-core is a dead tie at 102 for both. R20 single-core is also tied at 425. R23 single-core gives the Xeon a one-point edge at 1013 versus 1012. In absolute terms, the Core i7's higher boost clock (3.90 GHz versus 3.00 GHz) does not translate into a measured single-core advantage in these tests. The architecture gap between Haswell-EP and Sandy Bridge-E likely offsets the frequency difference, though the database does not provide per-architecture efficiency metrics.

The Core i7's only other benchmark in the database is Geekbench, where it records 3193 multi-core and 657 single-core. Since the Xeon has no Geekbench entry, that test does not appear in the head-to-head table. The six head-to-head results all favor the Xeon, giving it a 6-0 win tally. But a 0.1% margin is not a real-world performance gap; it is a statistical tie. The practical takeaway is that both CPUs deliver nearly identical Cinebench performance, with the Xeon's extra cores barely compensating for the Core i7's clock speed deficit.

FAQ

Q: Which CPU is faster in multi-core Cinebench R23?

A: The Intel Xeon E5-2628 v3 scores 7179, while the Intel Core i7-3960X scores 7170. The Xeon leads by 0.1%.

Q: Do the two CPUs have identical single-core performance?

A: In Cinebench R15 and R20, both score 102 and 425 respectively, a perfect tie. In R23, the Xeon leads by one point at 1013 versus 1012.

Q: Does the Core i7-3960X have any benchmark where it wins?

A: In the head-to-head benchmark set, the Core i7 wins zero tests. It does have a Geekbench result (3193 multi-core, 657 single-core), but the Xeon has no Geekbench score in the database, so no comparison is possible.

Q: Which CPU supports ECC memory?

A: Only the Intel Xeon E5-2628 v3 supports ECC memory. The Core i7-3960X does not.

Q: What are the memory types for each CPU?

A: The Xeon uses DDR4 with quad-channel support and 68.3 GB/s bandwidth. The Core i7 uses DDR3 with quad-channel support and 51.2 GB/s bandwidth.

Q: Which CPU has more cores and threads?

A: The Xeon has 8 cores and 16 threads. The Core i7 has 6 cores and 12 threads.

Architecture Differences

The two CPUs come from different Intel architectures and microarchitectures. The Xeon E5-2628 v3 uses the Haswell architecture on the Haswell-EP codename, built on a 22 nm process with 2,600 million transistors on a 356 mm² die. The Core i7-3960X uses the Sandy Bridge architecture on the Sandy Bridge-E codename, built on a 32 nm process with 2,270 million transistors on a larger 435 mm² die. The newer 22 nm node gives the Xeon a density advantage, despite having fewer transistors overall.

The Xeon's cache layout is larger: it has 20 MB of shared L3 cache, while the Core i7 has 15 MB. Both share the same per-core L1 (64 KB) and L2 (256 KB) sizes. The Xeon's extra L3 capacity likely helps in workloads with large working sets, though the benchmark data does not isolate cache effects specifically.

Memory support is a major architectural split. The Xeon uses DDR4 with a quad-channel memory bus and 68.3 GB/s peak bandwidth. The Core i7 uses DDR3 with the same quad-channel bus but only 51.2 GB/s peak bandwidth. The Xeon also supports ECC memory, while the Core i7 does not. This makes the Xeon the only one of the two suitable for error-checking memory configurations in servers or workstations.

Both CPUs expose the same PCIe configuration: Gen 3 with 40 CPU-only lanes. Neither has integrated graphics, so both require a discrete GPU. The Xeon targets the server/workstation market segment, while the Core i7 is a desktop part. The Xeon's multiplier is locked; the Core i7's is unlocked, reflecting its "Extreme" desktop positioning.

Specification Differences

The following table lists only the fields where the two processors differ, drawn directly from the database records.

| Specification | Intel Xeon E5-2628 v3 | Intel Core i7-3960X |

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

| Cores | 8 | 6 |

| Threads | 16 | 12 |

| Base clock | 2.50 GHz | 3.30 GHz |

| Boost clock | 3.00 GHz | 3.90 GHz |

| TDP | 85 W | 130 W |

| Socket | Intel Socket 2011-3 | Intel Socket 2011 |

| Architecture | Haswell | Sandy Bridge |

| Codename | Haswell-EP | Sandy Bridge-E |

| Process node | 22 nm | 32 nm |

| Transistors | 2,600 million | 2,270 million |

| Die size | 356 mm² | 435 mm² |

| L3 cache | 20 MB (shared) | 15 MB (shared) |

| Memory support | DDR4 | DDR3 |

| Memory bandwidth | 68.3 GB/s | 51.2 GB/s |

| ECC memory | Yes | No |

| Market segment | Server/Workstation | Desktop |

| Release date | 2014-09-07 | 2011-11-13 |

| Launch MSRP | None listed | $990 |

| Multiplier unlocked | No | Yes |

| Part number | SR201 | SR0H9SR0KF |

The Core i7-3960X has the higher clock speeds by a wide margin: 0.80 GHz on base and 0.90 GHz on boost. But it also draws 45 W more power (130 W versus 85 W). The Xeon compensates with two extra cores, four extra threads, more L3 cache, a newer process node, DDR4 support, and ECC capability. The Core i7's launch MSRP of $990 is listed in the database, while the Xeon has no recorded launch MSRP. The Core i7 is also the only one with an unlocked multiplier, allowing manual overclocking if the motherboard supports it. Both are end-of-life production parts, but the Xeon launched roughly three years later.