Intel Core i7-2720QM vs Intel Xeon E5640 Comparison

FAQ

Q: Which processor has the higher base clock speed?

A: The Intel Xeon E5640 has a base clock of 2.67 GHz, while the Intel Core i7-2720QM has a base clock of 2.20 GHz.

Q: Which processor has the higher boost clock speed?

A: The Intel Core i7-2720QM has a boost clock of 3.30 GHz, compared to 2.93 GHz for the Intel Xeon E5640.

Q: How do the two processors compare in Cinebench R23 multi-core performance?

A: The Intel Core i7-2720QM scores 3417 in Cinebench R23 multi-core, which is 3.3% ahead of the Intel Xeon E5640's score of 3303.

Q: Do both processors have the same core and thread counts?

A: Yes, both processors feature 4 cores and 8 threads.

Q: Which processor supports ECC memory?

A: The Intel Xeon E5640 supports ECC memory, while the Intel Core i7-2720QM does not.

Q: What is the difference in thermal design power between the two?

A: The Intel Xeon E5640 has a TDP of 80 watts, while the Intel Core i7-2720QM has a TDP of 45 watts.

Architecture Differences

The Intel Xeon E5640 and Intel Core i7-2720QM represent two distinct architectural generations from Intel, despite both being built on the same 32 nm process node. The Xeon E5640 belongs to the Westmere family, specifically the Westmere-EP variant, while the Core i7-2720QM is a Sandy Bridge design. This architectural split leads to several notable differences in how each processor approaches its workload.

The Xeon E5640 is built for the server and workstation market segment, using the Intel Socket 1366 platform. Its Westmere-EP architecture features a shared L3 cache of 12 MB, which is double the 6 MB shared L3 cache found in the Core i7-2720QM. The Core i7-2720QM, in contrast, targets the mobile segment and uses the Intel BGA 1224 socket, reflecting its laptop-oriented design.

The cache hierarchy is otherwise identical in structure: both processors have 64 KB of L1 cache per core and 256 KB of L2 cache per core. The transistor counts are nearly the same, with the Xeon E5640 at 1,170 million transistors and the Core i7-2720QM at 1,160 million. Die size differs slightly, with the Xeon E5640 measuring 239 mm² and the Core i7-2720QM at 216 mm².

Memory support marks a major divergence. The Xeon E5640 supports DDR3 memory with a triple-channel memory bus and includes ECC memory capability, making it suitable for error-sensitive server workloads. The Core i7-2720QM uses a dual-channel memory bus and lacks ECC support. The Core i7-2720QM also integrates Intel HD 3000 graphics, while the Xeon E5640 has no integrated graphics, a feature typical of server processors that rely on discrete graphics.

The Xeon E5640 specifies PCIe Gen 2 support, while the Core i7-2720QM does not list a PCIe version in the database. Both processors have locked multipliers, meaning neither can be overclocked via multiplier adjustment. The release dates differ by roughly nine months, with the Xeon E5640 arriving in March 2010 and the Core i7-2720QM in January 2011.

The Verdict

The benchmark data consistently favors the Intel Core i7-2720QM across all recorded tests, but the margins are narrow. In every Cinebench workload, the Core i7-2720QM wins by between 3.3% and 3.5%. The average benchmark score tells a slightly different story: the Xeon E5640 has an average score of 1137, while the Core i7-2720QM sits at 1128. This places the Xeon E5640 marginally ahead in the aggregate, despite losing every head-to-head test.

Both processors occupy the same percentile position at 32, indicating they perform similarly relative to all CPUs in the database. The nearest rivals for each processor reinforce this parity. The Xeon E5640's closest competitor is the AMD Athlon Silver PRO 3125GE at a delta of -0.1%, while the Core i7-2720QM's closest rival is the Intel Core i7-3612QM at -0.1% as well.

For users prioritizing raw compute in multi-threaded tasks, the Core i7-2720QM is the better choice based on head-to-head results. It wins every Cinebench test, including single-core and multi-core variants. The Xeon E5640, however, offers ECC memory support and triple-channel memory bandwidth, which are critical for server and workstation environments where data integrity and memory throughput matter more than a few percentage points of CPU performance.

The choice ultimately depends on platform requirements. The Core i7-2720QM targets mobile systems with its BGA 1224 socket and 45-watt TDP, making it suitable for laptops where power efficiency is paramount. The Xeon E5640 targets Socket 1366 server motherboards, where its 80-watt TDP and ECC support align with enterprise expectations. Neither processor is unlocked, so overclocking is not a factor in the decision.

Specification Differences

The Intel Xeon E5640 and Intel Core i7-2720QM differ across several key specification fields, even though they share the same core and thread counts.

Clock speeds: The Xeon E5640 has a base clock of 2.67 GHz and a boost clock of 2.93 GHz. The Core i7-2720QM has a lower base clock of 2.20 GHz but a significantly higher boost clock of 3.30 GHz.

TDP: The Xeon E5640 draws 80 watts, while the Core i7-2720QM draws 45 watts. This 35-watt difference reflects the mobile versus server design targets.

Socket: The Xeon E5640 uses Intel Socket 1366, while the Core i7-2720QM uses Intel BGA 1224.

Architecture and codename: The Xeon E5640 is based on Westmere (Westmere-EP), while the Core i7-2720QM is based on Sandy Bridge.

Process node: Both use 32 nm, but the transistor counts and die sizes differ slightly: 1,170 million transistors and 239 mm² for the Xeon E5640, versus 1,160 million transistors and 216 mm² for the Core i7-2720QM.

Cache: The L1 and L2 caches are identical at 64 KB and 256 KB per core respectively. The L3 cache differs significantly: 12 MB shared on the Xeon E5640 versus 6 MB shared on the Core i7-2720QM.

Memory: The Xeon E5640 supports DDR3 with a triple-channel memory bus and ECC memory. The Core i7-2720QM uses a dual-channel memory bus and does not support ECC. The Core i7-2720QM does not list DDR3 support in the database.

Graphics: The Core i7-2720QM includes integrated Intel HD 3000 graphics. The Xeon E5640 has no integrated graphics.

PCIe: The Xeon E5640 lists PCIe Gen 2 support. The Core i7-2720QM does not list a PCIe version.

Market segment: The Xeon E5640 targets server and workstation systems. The Core i7-2720QM targets mobile devices.

Part number: The Xeon E5640 carries the part number SLBVC, while the Core i7-2720QM carries SR00W.

Head-to-Head Benchmarks

The head-to-head benchmark results show a clean sweep for the Intel Core i7-2720QM, though the margins are consistently tight. Across five Cinebench tests, the Core i7-2720QM wins all of them with deltas ranging from -3.3% to -3.5% relative to the Xeon E5640.

The smallest margin appears in Cinebench R15 multi-core, where the Core i7-2720QM scores 344 against the Xeon E5640's 332, a delta of -3.5%. This pattern repeats in Cinebench R20 multi-core, with the Core i7-2720QM at 1435 and the Xeon E5640 at 1387, a -3.3% difference. The single-core results follow the same trajectory: Cinebench R20 single-core shows the Core i7-2720QM at 202 versus 195 for the Xeon E5640, again -3.5%.

Cinebench R23 results mirror the R20 numbers. In multi-core, the Core i7-2720QM scores 3417 against 3303 for the Xeon E5640, a -3.3% delta. In single-core, the Core i7-2720QM posts 482 versus 466, also -3.3%. These consistent margins suggest that the Core i7-2720QM's higher boost clock of 3.30 GHz provides a modest but uniform advantage over the Xeon E5640's 2.93 GHz boost clock, despite the Xeon's higher base clock and larger L3 cache.

The Xeon E5640 does not win any of the five head-to-head tests. The Core i7-2720QM also has additional benchmark data not available for the Xeon E5640: Geekbench multi-core at 1535 and Geekbench single-core at 484. These scores are not part of the head-to-head comparison but contribute to the Core i7-2720QM's overall benchmark profile.

The average benchmark scores tell a complementary story. The Xeon E5640 has an average benchmark score of 1137, placing it among rivals such as the Intel Core i5-2550K and Intel Core i5-3570T, both at a delta of 0.1%. The Core i7-2720QM has an average score of 1128, with its closest rival being the Intel Core i5-3330S at a delta of 0%. The slightly higher average score for the Xeon E5640, despite losing all head-to-head tests, likely reflects the different benchmark sets included in each processor's average calculation.

In practical terms, the Core i7-2720QM offers a small but measurable performance edge in Cinebench workloads. The Xeon E5640 counters with platform-level advantages: ECC memory, triple-channel memory bandwidth, and a larger shared L3 cache. The benchmark data suggests that for raw CPU throughput in these specific tests, the Core i7-2720QM is the stronger performer, but the differences are small enough that platform features and system requirements will likely determine the better overall choice.