CPU Comparison

The Intel Core i7-3632QM and the Intel Xeon E5645 are both 2010s-era Intel processors, but they target completely different segments: one is a low-power mobile chip, the other a server/workstation part. Benchmark data shows a clear, if narrow, overall winner: the Xeon E5645 wins all six head-to-head Cinebench tests, with margins ranging from 3.4% to 4%. However, the i7-3632QM counters with a dramatically lower 35W TDP and a much newer architecture, making the choice between them entirely dependent on whether your priority is raw multi-threaded throughput or power efficiency in a mobile form factor.

Where Each One Wins

The Intel Xeon E5645 wins every single benchmark comparison in the data set. In Cinebench R15, it scores 421 versus 406 in multi-core (a 3.6% lead) and 59 versus 57 in single-core (3.4% ahead). The story repeats in Cinebench R20, where the Xeon posts 1758 multi-core against the i7's 1693 (3.7% ahead) and 248 single-core versus 238 (4% ahead). The largest relative gap is in Cinebench R20 single-core, where the Xeon's 4% advantage is the biggest margin of any test. In Cinebench R23, the Xeon maintains its dominance with 4187 multi-core versus 4033 (3.7% ahead) and 591 single-core versus 569 (3.7% ahead). The Xeon's wins come from its two additional cores and four additional threads: 6 cores and 12 threads versus 4 cores and 8 threads.

The Intel Core i7-3632QM wins where benchmarks do not measure: power consumption and platform mobility. Its 35W TDP is less than half of the Xeon's 80W TDP. This makes the i7 the only viable option for a laptop or other battery-powered device, as it uses the mobile-specific Intel Socket G2 (988B). The i7 also integrates Intel HD 4000 graphics, whereas the Xeon has no integrated graphics at all, meaning the Xeon requires a discrete GPU in any system. The i7 is also the newer part, released in late 2012 versus early 2010 for the Xeon.

Architecture Differences

The architectural gap between these two is significant, reflecting their different release dates and market positions. The i7-3632QM is built on Intel's Ivy Bridge architecture using a 22 nm process node, while the Xeon E5645 uses the older Westmere architecture on a 32 nm process. This process advantage gives the i7 a smaller die size (160 mm² versus 239 mm²) despite holding more transistors: 1,480 million versus 1,170 million. The i7's denser 22 nm process is the primary reason it can deliver competitive performance at a fraction of the power draw.

Cache configurations also differ substantially. The Xeon packs 12 MB of shared L3 cache, double the i7's 6 MB. Both share the same per-core L1 (64 KB) and L2 (256 KB) cache sizes. The Xeon's larger L3 cache is typical of server parts designed for larger working sets, while the i7's smaller cache reflects its mobile focus. Memory support diverges as well: the Xeon supports DDR3 memory with a triple-channel memory bus and ECC memory, while the i7 uses a dual-channel bus with no ECC support. The Xeon also exposes PCIe Gen 2, a feature not listed for the i7. The i7 features integrated Intel HD 4000 graphics; the Xeon has none.

FAQ

Q: Which processor is faster in multi-core workloads?

A: The Intel Xeon E5645 wins every multi-core Cinebench test. It leads by 3.6% in R15 (421 vs 406), 3.7% in R20 (1758 vs 1693), and 3.7% in R23 (4187 vs 4033).

Q: Does the newer architecture of the i7-3632QM overcome the Xeon's core advantage?

A: No. Despite being built on a newer 22 nm Ivy Bridge process versus the Xeon's 32 nm Westmere, the i7's 4 cores and 8 threads cannot match the Xeon's 6 cores and 12 threads in any benchmark. The Xeon wins all six head-to-head tests.

Q: Is the i7-3632QM suitable for a desktop workstation?

A: No. It uses the Intel Socket G2 (988B) mobile socket and is classified as a mobile processor. Its 35W TDP is designed for laptops. It also lacks ECC memory support, which is often required for workstation reliability.

Q: Can the Xeon E5645 be used without a dedicated graphics card?

A: No. The Xeon E5645 has no integrated graphics. Any system using it must have a separate discrete GPU. The i7-3632QM, by contrast, integrates Intel HD 4000 graphics.

Q: Which processor has more cache?

A: The Xeon E5645 has 12 MB of shared L3 cache, double the i7-3632QM's 6 MB. Both have identical 64 KB L1 and 256 KB L2 caches per core.

Q: What is the TDP difference between the two?

A: The i7-3632QM has a 35W TDP, while the Xeon E5645 has an 80W TDP. The i7 draws less than half the power of the Xeon.

Specification Differences

| Specification | Intel Core i7-3632QM | Intel Xeon E5645 |

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

| Cores | 4 | 6 |

| Threads | 8 | 12 |

| Base Clock | 2.20 GHz | 2.40 GHz |

| Boost Clock | 3.20 GHz | 2.67 GHz |

| TDP | 35 W | 80 W |

| Socket | Intel Socket G2 (988B) | Intel Socket 1366 |

| Architecture | Ivy Bridge | Westmere |

| Process Node | 22 nm | 32 nm |

| Transistors | 1,480 million | 1,170 million |

| Die Size | 160 mm² | 239 mm² |

| L3 Cache | 6 MB (shared) | 12 MB (shared) |

| Memory Bus | Dual-channel | Triple-channel |

| ECC Memory | No | Yes |

| PCIe | Not listed | Gen 2 |

| Integrated Graphics | Intel HD 4000 | None |

| Market Segment | Mobile | Server/Workstation |

| Release Date | 2012-10-18 | 2010-03-15 |

Head-to-Head Benchmarks

The Xeon E5645 sweeps all six benchmark comparisons, but the margins are consistently narrow. In Cinebench R15 multi-core, the Xeon scores 421 versus 406, a 3.6% advantage. The single-core R15 test shows a similar 3.4% gap (59 vs 57). Moving to Cinebench R20, the Xeon's multi-core lead is 3.7% (1758 vs 1693), and its single-core lead grows to 4% (248 vs 238), the largest single-test margin in the entire comparison. Cinebench R23 results mirror the pattern: the Xeon wins multi-core by 3.7% (4187 vs 4033) and single-core by 3.7% (591 vs 569).

The consistency of these results is notable. Every single test, regardless of workload type (single-core or multi-core) or Cinebench version (R15, R20, or R23), produces a win for the Xeon with a delta between 3.4% and 4%. The i7-3632QM never comes within 3% of the Xeon in any test. The Xeon's 2 additional cores and 4 additional threads provide a steady baseline advantage, while its higher base clock (2.40 GHz vs 2.20 GHz) helps in single-threaded tests, even though its boost clock is significantly lower (2.67 GHz vs 3.20 GHz). The i7's higher boost clock is insufficient to close the single-core gap in any Cinebench test.

Both processors sit at the 34th percentile of all CPUs in the benchmark database, and their average benchmark scores are nearly identical: 1219 for the i7 and 1211 for the Xeon. The Xeon's nearest rival is the Intel Core i3-7300T with an identical average score of 1211 (0% delta), while the i7-3632QM's closest competitor is the Intel Core i5-2500 at 1220 (a -0.1% delta). These figures confirm that in aggregate performance, the two chips are statistically indistinguishable, even though the Xeon wins every individual Cinebench test.

The Verdict

The benchmark data is unambiguous: the Intel Xeon E5645 is the faster processor in every measured workload. Its 6 cores and 12 threads, combined with a higher base clock and double the L3 cache, give it a consistent 3.4% to 4% edge over the i7-3632QM across all Cinebench R15, R20, and R23 tests. If your sole criterion is raw CPU throughput, the Xeon is the clear choice.

However, the i7-3632QM wins the other half of the equation. Its 35W TDP is less than half the Xeon's 80W, making it the only option for mobile systems. It also integrates Intel HD 4000 graphics, eliminating the need for a separate GPU, and uses a much newer 22 nm Ivy Bridge architecture that delivers nearly equivalent performance with far less power. The i7 also supports a newer memory bus (dual-channel) and smaller die size, though it sacrifices ECC support and triple-channel memory bandwidth.

Choose the Xeon E5645 if you are building a server or workstation where power draw is secondary to multi-threaded performance and where ECC memory and PCIe Gen 2 are required. The Xeon's end-of-life production status and Socket 1366 platform are constraints, but its benchmark wins are real. Choose the i7-3632QM if you need a mobile processor with integrated graphics and minimal power consumption. The 3.4% to 4% performance deficit is a small price for a chip that uses 45 fewer watts and fits in a laptop socket. The data shows no wrong answer, only the wrong use case.