AMD Athlon PRO 3045B vs Intel Xeon W3520 Comparison

The AMD Athlon PRO 3045B and the Intel Xeon W3520 are two very different processors from different eras, aimed at entirely different market segments. The Athlon is a modern, low-power mobile part built on a 14nm process, while the Xeon is an older, high-power server/workstation chip on 45nm. The benchmark data shows a clear, consistent winner across every tested workload, but the underlying specifications tell a story of two completely different design philosophies.

Head-to-Head Benchmarks

The Intel Xeon W3520 wins all five head-to-head benchmark comparisons, but the margins are surprisingly narrow given the generational gap. In Cinebench R15 multi-core, the Xeon scores 252 against the Athlon's 237, a 6% advantage. That pattern holds for Cinebench R20 multi-core, where the Xeon posts 1052 versus 988, a 6.1% lead. The single-core results are similarly close: in Cinebench R20 single-core, the Xeon's 148 edges out the Athlon's 139 by 6.1%, and in Cinebench R23 single-core, the Xeon wins 353 to 332, a 5.9% margin. The largest delta in the entire set is the R23 multi-core test, where the Xeon's 2505 beats the Athlon's 2354 by 6%.

What stands out here is not the Xeon's dominance, but its inability to leverage its extra cores for a bigger win. The Xeon has twice the cores (4 vs 2) and twice the threads (8 vs 4), yet it only manages a 6% advantage in multi-threaded workloads. This suggests the Athlon's Zen architecture and higher boost clock (3.20 GHz vs 2.93 GHz) are doing substantial work to close the gap. In single-core tests, the Xeon's higher base clock (2.67 GHz vs 2.30 GHz) gives it the edge, but again by only roughly 6%.

The average benchmark score tells a similar story: the Athlon averages 872 across all tests, while the Xeon averages 862. That puts the Athlon 0.1% ahead of the Intel Atom C5315 (871) and 0.6% ahead of the Intel Core i7-3540M (867) and Intel Xeon X3460 (866), while trailing the Intel Core i3-5157U (877) by 0.5%. The Xeon's average of 862 places it 0.1% behind the Intel Core i5-3470T (863), 0.2% ahead of the AMD A8-7650K (860), and 0.3% ahead of the Intel Core i7-4500U (859). Both processors sit at the 23rd percentile of all CPUs, meaning they are in the same performance tier despite their architectural differences.

Where Each One Wins

The Intel Xeon W3520 wins every single benchmark in the comparison, so on raw performance, it is the clear choice. Its wins are consistent across both single-core and multi-core tests, with all deltas clustered tightly between 5.9% and 6.1%. If the workload is purely CPU-bound and the system can handle the power draw, the Xeon is faster in every measured scenario.

However, the AMD Athlon PRO 3045B wins in areas that are not captured by the benchmark scores. It is a 15W part versus the Xeon's 130W TDP, making it dramatically more power-efficient. The Athlon also uses DDR4 memory with dual-channel support and a memory bandwidth of 38.4 GB/s, while the Xeon uses DDR3 with triple-channel support and no listed bandwidth figure. The Athlon has integrated Radeon Vega graphics (2 compute units), whereas the Xeon has no integrated graphics at all. For a system that needs to run without a discrete GPU, or one constrained by power and cooling, the Athlon is the only viable option.

The Athlon also has a modern socket (AMD Socket FP5) and is still in active production, while the Xeon uses the legacy Intel Socket 1366 and is end-of-life. For new builds, the Athlon offers a path forward; the Xeon requires old hardware. The Athlon's 14nm process and 3,500 million transistors on a 148 mm² die also contrast sharply with the Xeon's 45nm process, 731 million transistors, and 263 mm² die, reflecting a massive efficiency advantage for the newer chip.

FAQ

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

A: The Intel Xeon W3520 wins all multi-core benchmarks. It scores 252 in Cinebench R15, 1052 in Cinebench R20, and 2505 in Cinebench R23, compared to the Athlon's 237, 988, and 2354 respectively. The Xeon's advantage is consistently around 6%.

Q: Is the Athlon PRO 3045B competitive in single-core performance?

A: It is close but loses every single-core test. The Xeon scores 148 in Cinebench R20 single-core and 353 in Cinebench R23 single-core, while the Athlon scores 139 and 332. The Xeon leads by 5.9% to 6.1% in these tests.

Q: How do their average benchmark scores compare?

A: The Athlon has a higher average benchmark score of 872, versus the Xeon's 862. This places the Athlon slightly above the Xeon in overall average performance, despite losing every head-to-head test.

Q: Do both processors support ECC memory?

A: Yes, both the AMD Athlon PRO 3045B and the Intel Xeon W3520 support ECC memory. This makes both suitable for error-sensitive workloads.

Q: Which processor has a higher TDP?

A: The Intel Xeon W3520 has a TDP of 130W, which is significantly higher than the AMD Athlon PRO 3045B's 15W. The Xeon requires substantially more power and cooling.

Q: What is the production status of each chip?

A: The AMD Athlon PRO 3045B is listed as active in production, while the Intel Xeon W3520 is end-of-life. The Xeon was released on March 29, 2009.

Specification Differences

The two processors differ in nearly every fundamental specification. The AMD Athlon PRO 3045B has 2 cores and 4 threads, while the Intel Xeon W3520 has 4 cores and 8 threads. The Athlon's base clock is 2.30 GHz with a boost clock of 3.20 GHz; the Xeon's base clock is higher at 2.67 GHz, but its boost clock is lower at 2.93 GHz. TDP is a major divergence: the Athlon draws 15W, the Xeon draws 130W.

Memory support differs completely. The Athlon uses DDR4 with a dual-channel bus and a memory bandwidth of 38.4 GB/s. The Xeon uses DDR3 with a triple-channel bus and no listed memory bandwidth. Both support ECC memory. The Athlon has integrated Radeon Vega graphics (2 compute units); the Xeon has no integrated graphics.

The Athlon uses AMD Socket FP5, while the Xeon uses Intel Socket 1366. The Athlon's PCIe support is Gen 3 with 12 lanes (CPU only), while the Xeon's is Gen 2 with no lane count specified. The Athlon's part number is YM3045C4T2OFG; the Xeon's is SLBEW. Neither processor has an unlocked multiplier.

Architecture Differences

The architectural gap is generational. The AMD Athlon PRO 3045B is built on the Zen architecture, codenamed Dali, using a 14nm process at GlobalFoundries. It packs 3,500 million transistors into a 148 mm² die. Its cache layout is 96 KB of L1 per core, 512 KB of L2 per core, and 4 MB of shared L3 cache.

The Intel Xeon W3520 uses the Nehalem architecture, codenamed Bloomfield, on a 45nm process at Intel. It contains 731 million transistors on a 263 mm² die. Its cache is smaller per core: 64 KB of L1 per core and 256 KB of L2 per core, but it has a larger 8 MB of shared L3 cache.

The Athlon's memory controller is dual-channel for DDR4, while the Xeon's is triple-channel for DDR3. The Athlon integrates a Radeon Vega GPU, while the Xeon relies on a discrete graphics card. The Athlon is a mobile-market chip with a 15W TDP, designed for efficiency; the Xeon is a server/workstation chip with a 130W TDP, designed for sustained throughput. The Athlon's 14nm process gives it a massive transistor density and efficiency advantage, while the Xeon's older 45nm process and larger die size reflect its 2009 origins.

The Verdict

The data presents a clear performance winner: the Intel Xeon W3520 beats the AMD Athlon PRO 3045B in every single benchmark, with margins between 5.9% and 6.1%. If raw compute performance is the only criterion, the Xeon is the faster processor. It also offers double the cores and threads, which should theoretically make it far more capable in heavily threaded applications, though the benchmark results show only a modest 6% lead in multi-core tests.

However, the Athlon PRO 3045B is the more practical choice for modern systems. It is actively in production, uses a current socket, supports DDR4 memory, and includes integrated graphics. Its 15W TDP is a fraction of the Xeon's 130W, making it suitable for compact, low-power builds where the Xeon would require a substantial cooling solution and power delivery. The Athlon's higher average benchmark score (872 vs 862) also indicates that across a broader set of workloads, it holds up well.

The decision comes down to context. For someone building a new, efficient system with a focus on modern features and low power consumption, the AMD Athlon PRO 3045B is the sensible pick. For someone with an existing 1366 platform or a need for maximum multi-threaded performance at any power cost, the Intel Xeon W3520 is faster in every measured test. Both sit at the 23rd percentile of all CPUs, so neither is a high-performance part by current standards, but the Xeon's age and end-of-life status make the Athlon the safer long-term investment. The Xeon wins on paper; the Athlon wins on practicality.