AMD Athlon X4 850

The AMD Athlon X4 850 is a 28nm Steamroller-based quad-core processor for the FM2+ socket, featuring four threads, a base clock of 3.20 GHz, and a boost clock of 3.90 GHz. It targets the legacy desktop segment with DDR3 memory support and a 65W TDP, positioning it as a straightforward, low-power option for older builds.

Benchmark Performance

The benchmark data places the Athlon X4 850 firmly in the entry-level performance tier. Its average benchmark score of 806 places it at the 21st percentile of all CPUs, meaning it outperforms roughly one in five processors in the database. This is not a processor designed for heavy lifting; rather, it delivers consistent, predictable results for basic computing tasks.

In multi-threaded workloads, the processor demonstrates modest capability. It scores 235 points in Cinebench R15 multi-core, 983 points in Cinebench R20 multi-core, and 2342 points in Cinebench R23 multi-core. These figures show a linear scaling pattern: the R20 score is roughly four times the R15 score, and the R23 score is roughly 2.4 times the R20 score, indicating stable performance across different benchmark generations without any unexpected throttling or efficiency cliffs.

The processor’s closest rival, the Intel Xeon X5482, posts an average score of 805, which is a negligible 0.1% difference. This effectively puts the two chips in a dead heat for overall average performance. The Intel Xeon X3440 scores 808, a 0.2% lead over the Athlon X4 850, while the Intel Core i7-870S scores 809, a 0.3% lead. The AMD A10-6800K rounds out the rival group with a score of 809, also 0.4% ahead. These deltas are so small that they fall within normal run-to-run variance; in practical terms, the Athlon X4 850 is performance-equivalent to all four of these rivals.

What stands out is the single-core performance relative to these rivals. The Cinebench R23 single-core score of 330 is comparatively weak, and the R20 single-core score of 138 reinforces this. The data suggests that the Athlon X4 850’s aggregate score is carried by its four physical cores, not by any single-thread strength. When comparing to the Xeon X5482, which is an older server part with a similar average score, the Athlon’s multi-threaded showing is likely competitive, but its single-thread results would lag behind more modern architectures.

Single-Thread vs Multi-Thread Behavior

The split between single-thread and multi-thread performance is stark. In Cinebench R23, the multi-core score of 2342 is roughly 7.1 times the single-core score of 330. For a true quad-core with perfect scaling, you would expect a multiplier of around 4.0. The fact that it exceeds this suggests either that the single-core boost clock is not being fully utilized in that specific test, or that the multi-core test benefits from the processor’s ability to maintain sustained clocks across all cores.

In Cinebench R20, the multi-core score of 983 is approximately 7.1 times the single-core score of 138, repeating the same ratio. This consistent 7.1x multiplier indicates that the processor’s multi-threaded efficiency is strong relative to its own single-thread capability, but that single-thread performance itself is a bottleneck. The boost clock of 3.90 GHz is present, but the Steamroller architecture’s per-core efficiency is lower than newer designs.

For real-world workloads, this means the Athlon X4 850 will handle multi-threaded tasks—like video encoding, batch image processing, or compiling—much better than its single-core scores suggest. Conversely, lightly-threaded applications such as older games, web browsers with a single heavy tab, or spreadsheet macros that are not multi-threaded will feel sluggish. The processor is effectively optimized for parallel throughput, not for snappy single-thread responsiveness.

The 7.1x ratio also implies that the processor’s four cores are well-utilized under multi-threaded loads, without significant contention for shared resources like L2 cache or memory bandwidth. The 4 MB of L2 cache is shared across the four cores, and the data indicates that scaling does not degrade as core count increases. This is a positive sign for a processor of this age, as some older multi-core designs show diminishing returns past two cores.

Power and Thermals

With a TDP of 65 watts, the Athlon X4 850 falls into a low-power class that is well-suited for compact desktops or systems with modest cooling solutions. This is a notable advantage over many of its rivals; for instance, the Intel Xeon X5482 is a server-class part with a much higher power draw, though the FACT PACK does not provide its exact TDP. The 65W figure means a standard air cooler with a small heatsink and fan is more than sufficient to keep temperatures in check.

The 28nm process node from GlobalFoundries is relatively mature, and the 2,411 million transistors on a 245 mm² die are packed at a moderate density. This architecture does not produce extreme heat density, so even a basic downdraft cooler or a low-profile cooler in a small form factor case should handle it without thermal throttling. The unlocked multiplier also allows for overclocking, but the 65W TDP suggests that pushing clocks significantly higher would require a better cooler to manage the additional heat.

The memory bus is dual-channel DDR3 with a bandwidth of 34.1 GB/s, which is adequate for the processor’s performance class. The lack of ECC memory support positions this as a consumer part, not a workstation chip. PCIe Gen 3 with 16 lanes from the CPU provides a solid foundation for a single graphics card, though modern GPUs may not fully saturate the bandwidth available.

The 65W TDP also has implications for system power supplies. A system built around this processor does not require a high-wattage PSU; a basic 300W to 400W unit would be ample, assuming a single mid-range GPU. This makes the Athlon X4 850 a practical choice for budget-conscious builders who already own DDR3 memory and an FM2+ motherboard, as it minimizes both upfront cost and ongoing power consumption.

FAQ

Q: How does the Athlon X4 850 compare to the Intel Xeon X5482?

A: The average benchmark scores are nearly identical, with the Xeon X5482 at 805 and the Athlon X4 850 at 806, a 0.1% difference. They are effectively tied in overall performance.

Q: What is the processor’s single-core performance like?

A: In Cinebench R23, the single-core score is 330, and in Cinebench R20 it is 138. These are low figures that indicate weak per-core performance, which will affect lightly-threaded tasks.

Q: Is this processor good for gaming?

A: The multi-core scores (e.g., 2342 in Cinebench R23) are passable for older or multi-threaded games, but the low single-core score of 330 will bottleneck modern titles that rely heavily on one or two threads.

Q: What memory does it support?

A: It supports dual-channel DDR3 memory with a bandwidth of 34.1 GB/s. ECC memory is not supported.

Q: Does it have an unlocked multiplier?

A: Yes, the multiplier is unlocked, allowing for overclocking. However, the 65W TDP means that significant overclocks will require a more capable cooler.

Q: What socket does it use?

A: It uses the AMD Socket FM2+ and is based on the Godaveri architecture (Steamroller cores) on a 28nm process.

How It Compares

Intel Xeon X5482: The Athlon X4 850 is a statistical tie with this older server processor, with only a 0.1% difference in average score (806 vs 805). The Athlon has a lower TDP and consumer-oriented features like DDR3 support and an unlocked multiplier, making it far more practical for a desktop build than a legacy Xeon.

Intel Xeon X3440: This rival holds a 0.2% lead over the Athlon X4 850 in average score (808 vs 806). The performance gap is negligible, but the X3440 is also a server part, so the Athlon’s advantage lies in its platform accessibility, not in raw speed.

Intel Core i7-870S: The i7-870S scores 809, a 0.3% edge over the Athlon. This is a low-power desktop chip, and the benchmark delta is so small that real-world differences would be imperceptible. The Athlon’s quad-core setup matches the i7’s capabilities in multi-threaded tasks, though the i7 may have better single-thread strengths not captured in the average score.

AMD A10-6800K: The A10-6800K is 0.4% ahead with a score of 809. This is the most direct rival, as both are AMD FM2+ parts. The Athlon X4 850 lacks integrated graphics (the FACT PACK shows null for iGPU), whereas the A10-6800K includes them, but the benchmark scores indicate the Athlon is essentially equal in CPU performance, making the choice dependent on whether you need an iGPU.

Who Should Consider It

The Athlon X4 850 is a niche product for users who already own an FM2+ motherboard and DDR3 memory, and who need a low-power quad-core for basic productivity. Its multi-threaded scores—983 in Cinebench R20 and 2342 in Cinebench R23—are sufficient for office applications, web browsing with many tabs, and light video editing or 3D rendering that can utilize all four cores. The 65W TDP makes it a strong candidate for a silent home server or a media center PC, where low heat output is a priority.

Gamers should be cautious. The single-core score of 330 in Cinebench R23 is a clear warning that modern game engines, which often rely on one or two fast threads, will not perform well. However, for older titles (pre-2015) or indie games that are multi-threaded, the processor can deliver playable frame rates with a modest GPU.

Content creators who work with batch operations—like rendering a series of still images or encoding multiple audio files—will find the multi-threaded performance acceptable, but the lack of L3 cache and the modest memory bandwidth of 34.1 GB/s will limit more demanding tasks like 4K video editing. The processor is end-of-life, so it should not be considered for new builds unless you are repurposing existing components. For anyone without a legacy FM2+ platform, the data suggests that more modern budget processors would offer better single-thread performance and similar multi-thread results, though the FACT PACK does not include those comparisons. Ultimately, the Athlon X4 850 is a serviceable workhorse for its intended era, but it is outclassed by the passage of time.