Intel Core i3-6320 vs Intel Xeon E5-1603 v3 Comparison

Head-to-Head Benchmarks

The recorded data shows a remarkably consistent margin across every Cinebench workload. The Intel Xeon E5-1603 v3 wins all six head-to-head comparisons, but the margins are narrow, ranging from 1% to 1.9%. The Core i3-6320 loses every match by no more than 2%, which places these two processors in a very tight performance band despite their different designs.

In Cinebench R15 multicore, the Xeon scores 382 against the i3's 378, a 1% advantage. The single-core result is closer in percentage terms but slightly larger in relative impact: 54 versus 53, a 1.9% lead for the Xeon. That single-core gap is the largest delta in the entire comparison, which is notable because the i3 has a substantially higher base clock of 3.90 GHz versus the Xeon's 2.80 GHz.

Moving to Cinebench R20, the pattern holds. The Xeon posts 1595 multicore against 1576 for the i3, a 1.2% edge. Single-core results are 225 versus 222, a 1.3% difference. The R23 suite repeats this almost exactly: 3798 versus 3753 in multicore (1.2%) and 536 versus 529 in single-core (1.3%). The consistency across all six tests suggests a stable, predictable performance relationship rather than workload-dependent swings.

The average benchmark scores in the database reflect this near-tie. The Xeon E5-1603 v3 averages 1098 across all recorded tests, while the Core i3-6320 averages 1085. The Xeon also holds a slightly higher percentile rank among all CPUs at 31 versus 30. In the nearest rival comparisons, the i3-6320 sits between the Core i5-2450P (1086, 0.1% ahead) and the Core i5-2320 (1083, 0.2% behind), while the Xeon matches the AMD PRO A10-8850B exactly at 1098 with a 0% delta. The Xeon's rival set also includes the Pentium 6805 and Core i5-3450S, both at 1099 and 0.1% behind the Xeon.

What the benchmark data does not show is any scenario where the Core i3 pulls ahead. The Xeon wins every single test, but the largest win is only 1.9%. For practical purposes, these two CPUs deliver nearly interchangeable Cinebench results. The real differentiators lie elsewhere: in architecture, memory support, platform features, and intended market segment.

Architecture Differences

The Core i3-6320 is built on Intel's 14 nm Skylake architecture, while the Xeon E5-1603 v3 uses the 22 nm Haswell-EP design. This process gap is significant for power efficiency. The i3 draws 51 W TDP, while the Xeon consumes 140 W. The Xeon's larger process node and higher power budget reflect its workstation and server heritage, not a performance advantage in these specific tests.

The transistor and die size figures show the scale difference. The Xeon packs 2,600 million transistors on a 356 mm² die, while the i3 uses 1,400 million transistors on a 150 mm² die. The Xeon's larger silicon area accommodates four physical cores and a much bigger shared L3 cache. The i3 has two physical cores with Hyper-Threading, yielding four threads. The Xeon also has four threads, but from four physical cores without Hyper-Threading. Both processors present four logical threads to the operating system, which explains their similar Cinebench multicore scores.

Cache configurations diverge sharply. The i3 provides 4 MB of shared L3 cache, while the Xeon offers 10 MB of shared L3. L1 and L2 caches are identical per core: 64 KB L1 and 256 KB L2 for each core. The Xeon's larger L3 does not translate into a meaningful benchmark advantage in these tests, but it can matter for certain workload patterns that the database's Cinebench suite does not capture.

Memory support is a major architectural split. Both support DDR4, but the i3 runs dual-channel with 34.1 GB/s of memory bandwidth, whereas the Xeon runs quad-channel with 59.7 GB/s. That is a 75% bandwidth advantage for the Xeon on paper. The Xeon also supports ECC memory, a critical feature for error-sensitive workstation and server environments. The i3 does not support ECC. The Xeon provides 40 PCIe Gen 3 lanes from the CPU, while the i3 offers 16 lanes. This makes the Xeon far more expandable for multiple GPUs or high-speed storage controllers.

The i3 includes integrated graphics in the form of Intel HD 530, while the Xeon has no integrated graphics at all. A workstation using the Xeon requires a discrete GPU. The i3 can operate with just the integrated graphics, though its market segment is desktop rather than server. The Xeon targets server and workstation use, and the i3 targets desktop use. The Xeon is marked end-of-life, while the i3 remains active in production status.

The sockets are incompatible. The i3 uses Intel Socket 1151, while the Xeon uses Intel Socket 2011-3. This means platform choice is a binary decision: you cannot swap between them without changing the motherboard. The Xeon's platform is built for multi-socket server environments and large memory configurations, while the i3's platform is mainstream desktop.

FAQ

Q: Which processor wins in Cinebench R23 multicore?

A: The Intel Xeon E5-1603 v3 scores 3798 versus the Core i3-6320's 3753, a 1.2% advantage for the Xeon.

Q: How large is the single-core performance gap?

A: The Xeon leads in every single-core test. The largest margin is in Cinebench R15 single-core, where the Xeon scores 54 against the i3's 53, a 1.9% difference. In R20 and R23, the gap is 1.3%.

Q: Does the Core i3's higher clock speed compensate for fewer cores?

A: The i3 runs at 3.90 GHz base versus the Xeon's 2.80 GHz, but the Xeon still wins all six benchmarks. The Xeon's four physical cores and larger cache offset the clock disadvantage in the recorded tests.

Q: Can the Core i3 support ECC memory?

A: No. The database lists ECC memory support as false for the i3-6320. The Xeon E5-1603 v3 supports ECC memory, which is a key differentiator for server and workstation reliability requirements.

Q: What is the memory bandwidth difference?

A: The Xeon provides 59.7 GB/s through quad-channel DDR4, while the i3 provides 34.1 GB/s through dual-channel DDR4. This is a substantial bandwidth advantage for the Xeon platform.

Q: Which processor has more PCIe lanes?

A: The Xeon E5-1603 v3 provides 40 PCIe Gen 3 lanes from the CPU, whereas the Core i3-6320 provides 16 lanes. This makes the Xeon more suitable for multi-GPU or high-expansion workstation builds.

The Verdict

The benchmark data presents a straightforward conclusion: the Intel Xeon E5-1603 v3 outperforms the Intel Core i3-6320 in every recorded Cinebench test, but only by a narrow margin. The largest single win is 1.9%, and most results fall between 1% and 1.3%. For users who prioritize raw render performance in Cinebench-type workloads, the Xeon is the better choice based on the numbers alone.

However, the database also shows two processors with identical thread counts and nearly identical scores. The average benchmark scores differ by only 13 points out of roughly 1090, and the percentile ranks are 31 versus 30. In practical terms, these CPUs are performance peers in the tested workloads. The Xeon's advantage in L3 cache (10 MB versus 4 MB), memory bandwidth (59.7 GB/s versus 34.1 GB/s), ECC support, and PCIe lane count makes it the more capable platform for professional workloads beyond Cinebench, even though those specific advantages do not show up in these particular benchmark results.

The Core i3 has its own strengths. It consumes 51 W versus 140 W, runs on a smaller 14 nm process, includes integrated graphics, and uses the mainstream Socket 1151 platform. For desktop users who do not need ECC memory, quad-channel bandwidth, or 40 PCIe lanes, the i3 offers a lower-power and more integrated solution. The i3 also carries a more recent release date: 2015-08-31 versus the Xeon's 2014-09-07.

The data suggests that the Xeon is the pick for workstation and server environments where ECC memory, memory bandwidth, and expansion capability matter. The Core i3 is the pick for desktop builds where integrated graphics, lower power draw, and a mainstream socket are sufficient. The benchmark scores alone do not justify a strong preference for either CPU, but the platform-level differences in the database make the choice clear based on the intended use case.

Specification Differences

| Specification | Intel Core i3-6320 | Intel Xeon E5-1603 v3 |

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

| Cores | 2 | 4 |

| Threads | 4 | 4 |

| Base Clock | 3.90 GHz | 2.80 GHz |

| TDP | 51 W | 140 W |

| Socket | Intel Socket 1151 | Intel Socket 2011-3 |

| Architecture | Skylake | Haswell-EP |

| Process Node | 14 nm | 22 nm |

| Transistors | 1,400 million | 2,600 million |

| Die Size | 150 mm² | 356 mm² |

| L3 Cache | 4 MB (shared) | 10 MB (shared) |

| Memory Bus | Dual-channel | Quad-channel |

| Memory Bandwidth | 34.1 GB/s | 59.7 GB/s |

| ECC Memory | No | Yes |

| PCIe Lanes | 16 | 40 |

| Integrated Graphics | Intel HD 530 | None |

| Market Segment | Desktop | Server/Workstation |

| Production Status | Active | End-of-life |

| Release Date | 2015-08-31 | 2014-09-07 |

| Part Number | SR2H9 | SR20K |

| Percentile vs All CPUs | 30 | 31 |

| Average Benchmark Score | 1085 | 1098 |