AMD Phenom II X2 B57

The AMD Phenom II X2 B57 is a dual-core desktop processor from the K10 architecture family, built on a 45 nm process and released in May 2010. With an average benchmark score of 368, it sits at the 4th percentile of all CPUs, placing it firmly in the entry-level segment of its era. The processor operates at a fixed base clock of 3.20 GHz with no boost capability, and its benchmark data reveals a distinct performance profile that separates single-threaded responsiveness from multi-threaded throughput.

Single-Thread vs Multi-Thread Behavior

The Phenom II X2 B57’s benchmark results show a pronounced gap between its single-core and multi-core performance. In Cinebench R20, the processor scores 63 points in single-core and 449 points in multi-core, yielding a ratio of approximately 7.1x. This indicates that the two physical cores scale almost linearly in heavily threaded workloads, with minimal overhead from thread synchronization or shared resource contention.

The Cinebench R23 results reinforce this pattern. The single-core score of 151 and multi-core score of 1071 produce a scaling factor of roughly 7.1x as well, consistent with the R20 data. For a dual-core processor without simultaneous multithreading, this near-perfect scaling suggests that the K10 architecture’s shared L3 cache (6 MB) and dual-channel memory interface do not become bottlenecks when both cores are active.

Real-world implications are clear. Applications that rely heavily on a single thread—such as older games, spreadsheet recalculation, or lightweight web browsing—will see performance roughly equal to the single-core score. In contrast, workloads that can utilize both cores, like video encoding or batch photo processing, will benefit from the full multi-core throughput. The absence of a boost clock means there is no transient single-core advantage; the 3.20 GHz frequency is constant regardless of load.

The 4th percentile ranking across all CPUs underscores that this processor is not competitive with modern designs. However, within its own generation, the dual-core configuration was a deliberate trade-off: higher clock speed per core compared to quad-core Phenom II parts, but fewer total threads. This makes the B57 better suited to lightly threaded tasks than to parallel workloads, where even entry-level quad-core processors would outperform it.

Power and Thermals

The Phenom II X2 B57 carries a TDP of 80 watts, which places it in a modest power class for a 45 nm desktop processor. For context, this TDP level requires a basic air cooler with a small heatsink and fan; no exotic cooling solution is necessary. The 80 W rating also implies that the processor does not demand premium power delivery components on the motherboard, making it compatible with a wide range of AM3 socket boards.

The 45 nm process node and 758 million transistors on a 258 mm² die suggest that heat density is manageable. The L3 cache, while shared and sizable at 6 MB, does not appear to cause thermal runaway under sustained load, as evidenced by the consistent multi-core scaling in benchmark results. The lack of a boost clock further simplifies thermal behavior—there are no sudden frequency spikes that would temporarily increase heat output.

For system builders, the 80 W TDP means that a low-profile cooler or a stock AMD cooler would suffice. The processor supports both DDR2 and DDR3 memory, which affects overall platform power but does not change the CPU’s thermal envelope. ECC memory support is present, which is unusual for a desktop part and may appeal to users running error-sensitive workloads, though this does not alter cooling requirements.

The end-of-life production status suggests that thermal performance is well understood, with no known anomalies reported in the benchmark data. The 80 W figure is a static specification; actual power draw will vary with workload, but the absence of boost means peak power is bounded by the base clock and the 45 nm process’s leakage characteristics.

Benchmark Performance

The benchmark data shows that the Phenom II X2 B57 performs nearly identically to its closest rivals, with deltas under 2% in all cases. In Cinebench R15 multi-core, the score of 107 is a direct measure of its two-core throughput. The Cinebench R20 multi-core score of 449 and R23 multi-core score of 1071 provide additional confirmation of this performance level, with the R23 test being the most demanding.

Against the Intel Celeron G550, the B57 is 0.4% faster in average benchmark score (368 vs. 367). This difference is negligible, falling within run-to-run variance. The Celeron G550 is a Sandy Bridge-era dual-core with lower clock speed, but the B57’s higher base clock compensates for architectural differences. The 0.4% delta effectively means the two processors are tied in overall performance.

The Intel Pentium G6950 is similarly matched, with the B57 being 0.5% faster (368 vs. 366). The Pentium G6950 features a higher clock speed than the Celeron but lacks hyper-threading, so its two physical cores align with the B57’s configuration. The 0.5% advantage is within noise, making the B57 and G6950 interchangeable in real-world performance.

The AMD A8-5545M, a mobile accelerated processing unit, is 0.9% faster than the B57 (372 vs. 368). This is a notable result because the A8-5545M has a lower TDP (typically 25 W) and integrated graphics, yet still edges out the B57 in raw CPU benchmarks. The delta is small, but it indicates that the B57’s 45 nm desktop design does not offer a significant performance advantage over a newer, more efficient mobile chip.

The Intel Celeron G1820TE is 1.1% faster than the B57 (372 vs. 368). This is the largest delta among the rivals, but still minimal. The G1820TE is a Haswell-era dual-core with a lower clock speed and reduced power consumption, yet its architectural efficiency allows it to slightly outperform the older K10 design. The 1.1% gap is not perceptible in everyday use.

Overall, the B57’s performance is tightly clustered with its rivals, all of which are entry-level dual-core processors. The 4th percentile ranking highlights that this cluster is at the very bottom of the modern performance spectrum. The average benchmark score of 368 is derived from a mix of single-core and multi-core tests, and the processor’s single-core scores (63 in R20, 151 in R23) are particularly low, dragging down its overall standing.

FAQ

Q: How many cores and threads does the AMD Phenom II X2 B57 have?

A: The processor has 2 cores and 2 threads, meaning it can handle only two simultaneous instruction streams without any form of multithreading.

Q: What is the base clock speed of the B57?

A: The base clock is 3.20 GHz, and there is no boost clock available, so the processor always runs at this fixed frequency.

Q: Does the B57 support ECC memory?

A: Yes, the processor supports ECC memory, which is a feature more commonly found in server or workstation parts, though the B57 is a desktop processor.

Q: What is the TDP of the B57 and what cooler does it need?

A: The TDP is 80 watts, which requires a basic air cooler; a low-profile or stock cooler is sufficient, and no high-end cooling solution is necessary.

Q: How does the B57 compare to the Intel Celeron G550?

A: The B57 is 0.4% faster in average benchmark score (368 vs. 367), making the two processors effectively equal in performance.

Q: What memory types does the B57 support?

A: The processor supports both DDR2 and DDR3 memory, operating in a dual-channel configuration, with a memory bandwidth of 21.3 GB/s.

Q: Is the B57’s multiplier unlocked?

A: No, the multiplier is locked, so overclocking via multiplier adjustment is not possible; any frequency increase would require raising the base clock.

How It Compares

vs. Intel Celeron G550: The B57 holds a razor-thin 0.4% average benchmark lead, with scores of 368 and 367 respectively. This parity means that in any given workload, the two processors will deliver nearly identical frame rates or render times. The B57’s higher clock speed offsets the Celeron’s newer architecture, but the practical difference is zero.

vs. Intel Pentium G6950: A 0.5% advantage for the B57 (368 vs. 366) places these two in the same performance tier. The Pentium G6950 has a similar dual-core configuration, and the B57’s larger L3 cache does not translate into a meaningful benchmark lead. Users upgrading from either processor would see no real improvement.

vs. AMD A8-5545M: The B57 is 0.9% slower than the A8-5545M (368 vs. 372). This is particularly telling because the A8-5545M is a mobile part with integrated graphics and lower power consumption. The B57’s desktop platform and higher TDP do not yield any performance benefit, indicating that the B57’s architecture is at a distinct disadvantage against a newer, more efficient design.

vs. Intel Celeron G1820TE: The B57 trails by 1.1% (368 vs. 372) against the G1820TE. This is the largest gap among its nearest rivals, though still within the margin of error for most benchmarks. The G1820TE’s Haswell architecture and lower clock speed demonstrate that IPC improvements over the K10 design are sufficient to overcome a frequency deficit. The B57’s performance is effectively tied with all four rivals, placing it in a crowded field of entry-level dual-core processors.