Intel Xeon X3450 vs Intel Xeon X5492 Comparison

Head-to-Head Benchmarks

The recorded data shows a remarkably consistent pattern across the entire Cinebench test suite: the Intel Xeon X5492 wins every single head-to-head comparison, but by margins that are almost negligible. In Cinebench R15 multicore, the X5492 scores 249 against the X3450's 245, a delta of 1.6%. The R20 multicore test shows the same story, with 1039 versus 1021, a 1.8% advantage. These are not the kind of gaps that would transform a workload from unusable to fluid; they are the kind of differences that appear within run-to-run variance on modern systems.

Single-core results follow the same trajectory. The X5492 records 146 in Cinebench R20 single-core, while the X3450 manages 144, a 1.4% edge. The R23 single-core test shows 349 against 343, a 1.7% margin. The largest recorded deltas in the entire comparison are the 1.8% figures in R20 and R23 multicore, and even those are slender.

When placed against the wider field, both processors occupy nearly identical territory. The X5492's average benchmark score is 852, placing it in the 23rd percentile of all CPUs in the database. The X3450 averages 837, sitting in the 22nd percentile. The nearest rivals for the X5492 include the Intel Core i5-5250U with an average score of 856 (a delta of -0.4%), the AMD Athlon X4 830 at 848 (0.4% ahead), and the Intel Core i5-2500T at 856 (-0.5%). The X3450's closest competitors are the Intel Core i5-5200U at 838 (-0.1%), the Intel Core i5-3380M at 838 (-0.2%), and the Intel Xeon X5470 at 839 (-0.3%). Both chips are effectively interchangeable with a cluster of low-power mobile and older desktop parts, sitting in the low quarter of the performance distribution.

The question the data raises is not which chip wins, because the X5492 wins all five recorded tests. The question is whether a 1.4% to 1.8% advantage across the board means anything in real-world use, especially when the architecture underneath each chip is fundamentally different.

Architecture Differences

The X5492 is a Core 2 architecture part, codenamed Harpertown, built for the Intel Socket 771 platform. It is a 45 nm design with 820 million transistors spread across a dual-die package, each die measuring 107 mm². The X3450, by contrast, is a Nehalem architecture chip, codenamed Lynnfield, on the Intel Socket 1156 platform. It is also 45 nm, but packs 774 million transistors onto a single 296 mm² die.

The cache layouts could not be more different. The X5492 uses a per-core L1 of 64 KB and a per-die L2 of 6 MB, with no L3 cache at all. The X3450 also has 64 KB of L1 per core, but its L2 is 256 KB per core, and it adds a shared 8 MB L3. That shared L3 is a significant architectural shift. It allows frequently accessed data to be pooled across all four cores, reducing the need to go to main memory. The X5492's larger L2 per die may help in some workloads, but it lacks the unified pool that the Nehalem design provides.

Threading is another major split. The X5492 offers 4 cores and 4 threads, meaning no hyper-threading. The X3450 offers 4 cores and 8 threads, doubling the logical thread count. In heavily threaded workloads that can exploit more than four threads, the X3450 has a structural advantage that the benchmark scores do not fully reflect, since those scores show the X5492 slightly ahead.

Memory support differs as well. The X5492 supports both DDR2 and DDR3 across a dual-channel bus, while the X3450 natively supports only DDR3, also on a dual-channel bus. The X3450 has a listed memory bandwidth of 21.3 GB/s. The X5492 has no explicit bandwidth figure in the database, so the comparison must remain qualitative: both are dual-channel, both support ECC memory, but the X3450's integrated memory controller (part of the Nehalem design) is a generational step forward.

The clock speeds tell the other side of the story. The X5492 runs at a base clock of 3.40 GHz with no boost clock listed. The X3450 has a base clock of 2.67 GHz and a boost clock of 3.20 GHz. So the X5492 starts higher and stays there, while the X3450 starts lower but can ramp up to a near-match under load. The X5492's higher sustained clock likely explains its small benchmark wins.

Where Each One Wins

The X5492 wins every recorded benchmark, but those wins are all within 1.8%. That means the X5492's advantage is in raw single-threaded and lightly threaded performance, where its 3.40 GHz base clock outruns the X3450's 3.20 GHz boost. In the Cinebench R23 single-core test, the X5492 scores 349 versus 343, a 1.7% lead. That is a direct clock-speed win.

The X3450's potential wins are not visible in the benchmark data, but the architecture points to them. With 8 threads versus 4, the X3450 can handle more concurrent work in properly threaded applications, even if the Cinebench suite does not show it. The shared 8 MB L3 cache and the Nehalem memory controller also suggest better memory latency behavior in cache-miss-heavy workloads. The 95 W TDP versus the X5492's 150 W TDP means the X3450 draws less power in sustained loads, which matters for dense server deployments.

In single-threaded or lightly threaded tasks, the X5492 is the pick. In multi-threaded workloads that scale beyond four threads, the X3450's architecture offers a path that the X5492 simply cannot follow, even if the recorded Cinebench numbers do not demonstrate it. The database says the X5492 wins all five tests, but the X3450's thread count and cache hierarchy make it the more future-proof choice for parallel software.

Specification Differences

The two processors differ on several core specification fields. The X5492 has 4 cores and 4 threads, while the X3450 has 4 cores and 8 threads. Base clocks are 3.40 GHz for the X5492 and 2.67 GHz for the X3450, with the X3450 also listing a boost clock of 3.20 GHz. The X5492 has no boost clock recorded.

Thermal design power: the X5492 is rated at 150 W, the X3450 at 95 W. The sockets differ: the X5492 uses Intel Socket 771, the X3450 uses Intel Socket 1156. The X5492 is a Core 2 part codenamed Harpertown, while the X3450 is Nehalem codenamed Lynnfield. Transistor counts are 820 million versus 774 million. Die sizes are 2x 107 mm² versus 296 mm².

Cache: the X5492 has 64 KB L1 per core and 6 MB L2 per die, with no L3. The X3450 has 64 KB L1 per core, 256 KB L2 per core, and 8 MB of shared L3. Memory support: the X5492 handles DDR2 and DDR3, the X3450 only DDR3. The X3450 has a listed memory bandwidth of 21.3 GB/s; the X5492 has none recorded. Both are dual-channel and support ECC.

PCIe generation is Gen 2 for both, but the X3450 specifies 16 lanes (CPU only), while the X5492 lists no lane count. The release dates are one year apart: the X5492 launched in September 2008, the X3450 in September 2009. Part numbers are SLBBD for the X5492 and SLBLD for the X3450. Both are end-of-life, neither has an unlocked multiplier, and neither has integrated graphics.

FAQ

Q: Which processor has the higher average benchmark score?

A: The Intel Xeon X5492 averages 852, while the Intel Xeon X3450 averages 837, a 15-point gap.

Q: How many threads does each processor support?

A: The X5492 supports 4 threads on 4 cores. The X3450 supports 8 threads on 4 cores, thanks to hyper-threading.

Q: What is the TDP difference between the two?

A: The X5492 is rated at 150 W, and the X3450 is rated at 95 W, a 55 W difference.

Q: Does either processor have a boost clock?

A: Only the X3450 lists a boost clock, at 3.20 GHz. The X5492 has no boost clock recorded.

Q: What is the L3 cache situation on each chip?

A: The X5492 has no L3 cache. The X3450 has 8 MB of shared L3 cache.

Q: Which chip wins the Cinebench R23 multicore test?

A: The X5492 scores 2475, and the X3450 scores 2431, giving the X5492 a 1.8% win.

The Verdict

The data points to a clear but narrow verdict: the Intel Xeon X5492 is the faster processor in every recorded benchmark, but its margins are slim. It wins Cinebench R15, R20, and R23 in both single-core and multicore modes, with deltas ranging from 1.4% to 1.8%. Its higher base clock of 3.40 GHz gives it a consistent edge in lightly threaded work, and that edge carries through to the multicore tests as well.

The X3450, however, offers structural advantages that the benchmarks do not capture. Its 8 threads versus 4, its shared 8 MB L3 cache, and its lower 95 W TDP versus 150 W make it a more balanced part for parallel workloads and power-conscious deployments. The X3450's 21.3 GB/s memory bandwidth and native DDR3 support also point to a more modern memory subsystem.

For anyone running single-threaded or lightly threaded applications on a Socket 771 platform, the X5492 is the better choice. For those building a Socket 1156 system with an eye toward multi-threaded software and lower power draw, the X3450 is the more rational pick. The benchmark scores say the X5492 is slightly ahead, but the architecture says the X3450 has more headroom. Both are end-of-life parts, so the decision hinges on what the existing platform supports. The recorded data shows a 1.8% performance gap, but the real-world gap in efficiency and threading is much wider.