Intel Core 2 Extreme QX9775 vs Intel Xeon X3450 Comparison

Where Each One Wins

The benchmark data paints a consistent picture: the Intel Xeon X3450 wins every single recorded head-to-head comparison. Across all five Cinebench tests, the Xeon X3450 takes the top spot, while the Core 2 Extreme QX9775 finishes behind in each instance. This is a clean sweep, with no test where the older Core 2 architecture manages to pull ahead.

The Xeon X3450's advantage is most pronounced in single-core workloads. In Cinebench R20 single-core, it scores 144 against 139 for the QX9775, a 3.6% lead. The R23 single-core test shows a similar 3% edge, with 343 versus 333. For workloads that depend heavily on per-thread performance, such as older applications or lightly threaded tasks, the Xeon X3450 is the better choice.

Multi-core tests tell the same story, though with slightly narrower margins. The Xeon X3450 leads by 2.9% in Cinebench R15, R20, and R23 multi-core tests. Its scores of 245, 1021, and 2431 respectively outpace the QX9775's 238, 992, and 2363. The gap remains consistent, suggesting the advantage comes from architectural efficiency rather than a single workload characteristic.

The Core 2 Extreme QX9775 does not have a single benchmark win in this dataset. Its strengths, such as a higher base clock of 3.20 GHz versus 2.67 GHz, do not translate into measured performance wins. The recorded data shows a processor that, despite its Extreme branding and higher base frequency, cannot overcome the architectural lead of the newer Xeon design.

Architecture Differences

These two processors represent different eras of Intel design. The Xeon X3450 uses the Nehalem architecture, specifically the Lynnfield die, built on a 45 nm process. The Core 2 Extreme QX9775 uses the older Core 2 architecture, codenamed Yorkfield, also on a 45 nm process. Both are built by Intel, so process node differences are not a factor here.

Core counts match at four physical cores, but threading separates them. The Xeon X3450 supports 8 threads through Hyper-Threading, while the QX9775 manages only 4 threads with no simultaneous multithreading. This doubles the thread count for the Xeon, a significant advantage in heavily threaded rendering workloads.

Cache configurations differ substantially. The Xeon X3450 has 64 KB of L1 cache per core, 256 KB of L2 cache per core, and a shared 8 MB L3 cache. The QX9775 also has 64 KB of L1 per core, but its L2 is organized as 6 MB per die, and it has no L3 cache at all. The Xeon's shared L3 cache provides a pool of fast memory accessible to all cores, while the QX9775 relies solely on its per-die L2.

Transistor counts show the architectural shift. The Xeon packs 774 million transistors on a 296 mm² die, while the QX9775 uses 820 million transistors spread across two dies of 107 mm² each. The dual-die design of the Yorkfield processor is less efficient at sharing data between cores, as each die has its own L2 cache with no unified cache layer.

Memory support also differs. The Xeon X3450 supports DDR3 with a dual-channel memory bus and a recorded bandwidth of 21.3 GB/s. The QX9775 supports DDR2, though the exact bandwidth depends on the motherboard. The Xeon's newer memory controller and higher bandwidth potential give it an edge in memory-intensive workloads.

Power characteristics are notable. The Xeon X3450 has a TDP of 95 watts, while the QX9775 draws 150 watts. This 55-watt difference means the Xeon delivers better performance while consuming less power, an important consideration for dense server deployments. The Xeon also uses PCIe Gen 2 with 16 CPU lanes, while the QX9775 uses the older PCIe Gen 1 standard.

Socket compatibility separates these parts completely. The Xeon X3450 uses Intel Socket 1156 with a Lynnfield-based design, while the QX9775 uses the older Intel Socket 771 platform. They are not interchangeable, and any platform decision must account for these different sockets.

Head-to-Head Benchmarks

The recorded Cinebench results show a narrow but consistent lead for the Xeon X3450. In Cinebench R15 multi-core, the Xeon scores 245 against 238 for the QX9775, a 2.9% advantage. This pattern repeats in Cinebench R20 multi-core, where 1021 beats 992, again by 2.9%. The consistency of this margin across different Cinebench versions suggests the performance gap is structural rather than workload-specific.

Cinebench R23 multi-core follows the same trend. The Xeon scores 2431, while the QX9775 manages 2363, a 2.9% lead. The multi-core advantage appears stable across all three Cinebench iterations, indicating that the Xeon's Hyper-Threading and cache architecture provide a reliable edge in fully threaded rendering tasks.

Single-core results show a slightly larger gap. In Cinebench R20 single-core, the Xeon scores 144 versus 139, a 3.6% lead. Cinebench R23 single-core shows 343 versus 333, a 3% difference. The larger single-core advantage is notable given that the QX9775 has a higher base clock of 3.20 GHz compared to the Xeon's 2.67 GHz base and 3.20 GHz boost. Despite the clock disadvantage, the Xeon's newer architecture wins single-threaded performance.

The aggregate benchmark scores reinforce this picture. The Xeon X3450 has an average benchmark score of 837, placing it in the 22nd percentile of all CPUs. Its nearest rival in the database is the Intel Core i5-5200U with nearly identical scores, just 0.1% behind. The Core 2 Extreme QX9775 has an average score of 813, also in the 22nd percentile, with its closest rival being the Intel Core i7-5550U at exactly 813.

The cumulative effect of these margins is modest but real. Across all five recorded tests, the Xeon X3450 leads by margins ranging from 2.9% to 3.6%. No single benchmark shows a dramatic gap, but the consistency across all tests makes the Xeon the clear winner in every measured scenario.

FAQ

Q: Which processor has more threads?

A: The Intel Xeon X3450 has 8 threads from its 4 cores, while the Core 2 Extreme QX9775 has only 4 threads, one per core. This doubles the thread count for the Xeon.

Q: Does the higher base clock of the QX9775 help it win any benchmarks?

A: No. The QX9775 has a base clock of 3.20 GHz compared to the Xeon's 2.67 GHz base and 3.20 GHz boost, but the Xeon wins all five recorded Cinebench tests despite the clock disadvantage.

Q: What is the largest performance margin between the two processors?

A: The largest margin is in Cinebench R20 single-core, where the Xeon X3450 leads by 3.6% with a score of 144 versus 139 for the QX9775.

Q: How do these processors compare to other CPUs in the database?

A: The Xeon X3450 has an average benchmark score of 837, placing it in the 22nd percentile. The QX9775 scores 813, also in the 22nd percentile. The Xeon's nearest rival is the Core i5-5200U at 838, while the QX9775's nearest rival is the Core i7-5550U at 813.

Q: Do both processors support ECC memory?

A: Yes, both the Xeon X3450 and the Core 2 Extreme QX9775 support ECC memory.

Q: Which processor has a larger cache?

A: The Xeon X3450 has 64 KB of L1 per core, 256 KB of L2 per core, and a shared 8 MB L3 cache. The QX9775 has 64 KB of L1 per core and 6 MB of L2 per die, but no L3 cache.

The Verdict

The data supports a clear conclusion: the Intel Xeon X3450 outperforms the Core 2 Extreme QX9775 in every recorded benchmark. The Xeon wins all five head-to-head tests, with margins ranging from 2.9% to 3.6%. Its average benchmark score of 837 exceeds the QX9775's 813, and both sit in the 22nd percentile of all CPUs.

For multi-threaded workloads, the Xeon's 8 threads versus 4 threads make it the stronger choice. Cinebench R15, R20, and R23 multi-core tests all show the Xeon ahead by 2.9%. The shared 8 MB L3 cache and dual-channel DDR3 support with 21.3 GB/s bandwidth further benefit memory-sensitive rendering tasks. The QX9775's dual-die design with separate 6 MB L2 caches and no L3 cache cannot match this architecture.

For single-threaded workloads, the Xeon also wins, despite the QX9775's higher base clock. The 3.6% lead in Cinebench R20 single-core and 3% lead in R23 single-core indicate that the Nehalem architecture delivers better instructions-per-clock than the older Core 2 design.

Users choosing between these processors should consider the Xeon X3450 if they need better performance across both single and multi-threaded tasks, lower power consumption at 95 watts versus 150 watts, and support for DDR3 memory. The QX9775 offers a higher base clock of 3.20 GHz and an unlocked multiplier, but neither advantage translates into benchmark wins in the recorded data.

The Xeon X3450 also carries a lower launch MSRP of $241 compared to the QX9775's $1499. For server or workstation deployments where the Intel Socket 1156 platform is viable, the Xeon provides superior measured performance in every recorded test. The QX9775 remains a capable desktop processor, but the benchmark results show it trailing the Xeon across the board.