AMD Athlon X4 845 vs AMD Opteron 3280 Comparison

The AMD Athlon X4 845 and the AMD Opteron 3280 present a rare case in hardware analysis: two processors built on fundamentally different architectures, with different core counts and cache hierarchies, yet producing benchmark results that are numerically indistinguishable. Across every Cinebench test in the database, both CPUs score identically, resulting in a 5-to-0 win count for the Athlon X4 845 solely by tie-breaking convention, not by performance superiority. The data indicates that these are not competing products with different strengths, but rather two implementations of nearly identical computational throughput, differentiated primarily by platform features and architectural lineage.

Where Each One Wins

The benchmark results show no meaningful performance separation between the two processors. In every single test — Cinebench R15 multicore, R20 multicore, R20 single-core, R23 multicore, and R23 single-core — the scores are exactly equal. The Athlon X4 845 is credited with all five wins, but each carries a deltaPct of 0, meaning there is no actual performance advantage. This is a statistical dead heat.

From a workload perspective, the data suggests that neither CPU has a domain where it pulls ahead. For single-threaded tasks, both score 190 in Cinebench R20 single-core and 453 in Cinebench R23 single-core. For multi-threaded workloads, both deliver 324 in Cinebench R15 multicore, 1350 in Cinebench R20 multicore, and 3215 in Cinebench R23 multicore. The Athlon X4 845 achieves this with four cores and four threads, while the Opteron 3280 uses eight cores and eight threads. The Opteron's additional cores do not translate into a multi-core win; conversely, the Athlon's higher clock speeds do not produce a single-core advantage. The verdict is that these processors are interchangeable in terms of raw compute output, making platform compatibility and feature support the only meaningful differentiators.

Architecture Differences

The architectural contrast between these two chips is stark. The Athlon X4 845 is built on the Excavator architecture with the Carrizo codename, fabricated on a 28 nm process at GlobalFoundries. It integrates 3,100 million transistors on a 250 mm² die. The Opteron 3280, by contrast, uses the K10 architecture with the Zurich codename, on a 32 nm process, also from GlobalFoundries, but with only 1,200 million transistors spread across a larger 315 mm² die.

The cache configurations diverge significantly. The Athlon X4 845 has 320 KB of L1 cache and 2 MB of L2 cache, with no L3 cache at all. The Opteron 3280 carries 384 KB of L1 cache, 8 MB of L2 cache, and an additional 8 MB of shared L3 cache. Despite the Opteron's far larger total cache footprint — 16 MB versus roughly 2.3 MB — the benchmark scores remain identical, suggesting that the Athlon's Excavator core design is more efficient at utilizing its smaller cache.

Clock speeds also differ. The Athlon runs at a 3.50 GHz base clock with a 3.80 GHz boost clock, while the Opteron operates at a 2.50 GHz base and 3.50 GHz boost. Both have a 65 W TDP, which is notable given the Opteron's additional cores and larger cache. Memory support is DDR3 for both, but the Athlon has a dual-channel bus with 34.1 GB/s bandwidth, while the Opteron manages 29.9 GB/s. The Athlon also supports PCIe Gen 3 with 8 CPU lanes, whereas the Opteron is limited to PCIe Gen 2. The Opteron can leverage integrated graphics on certain motherboards as a chipset feature, while the Athlon has no integrated graphics listed.

Platform compatibility is a major split. The Athlon X4 845 uses AMD Socket FM2+ and has an unlocked multiplier, making it a candidate for overclocking. The Opteron 3280 uses AMD Socket AM3+ and has a locked multiplier. The Athlon is from the Athlon (Carrizo) generation, released in February 2016, while the Opteron is from the Opteron (Zurich) generation, released in March 2012 — a four-year gap that explains the architectural differences.

Head-to-Head Benchmarks

The head-to-head data is remarkable for its uniformity. In Cinebench R15 multicore, both CPUs score 324, with a deltaPct of 0. The Athlon X4 845 is listed as the winner, but this is purely nominal. Moving to Cinebench R20 multicore, the scores are again tied at 1350. Single-core performance in Cinebench R20 shows both at 190. The most demanding test, Cinebench R23 multicore, produces identical scores of 3215 for both chips. Finally, Cinebench R23 single-core has both at 453.

Interpreting these numbers requires context from the nearestRivals data. Both CPUs have an average benchmark score of 1106, placing them at the 31st percentile of all CPUs. The nearest rivals include the AMD Opteron 4280 and AMD PRO A12-8870, each with an average score of 1107, reflecting a deltaPct of -0.1 relative to these chips. The AMD PRO A12-9800 scores 1104, a deltaPct of 0.2. This cluster of processors within a 3-point average score range indicates that the Athlon X4 845 and Opteron 3280 are not outliers; they sit in a densely packed performance tier where architectural differences do not yield measurable benchmark advantages.

The fact that the eight-core Opteron with 8 MB of L3 cache cannot outperform the four-core Athlon without L3 cache in multi-threaded tests is the most significant finding. It suggests that the Excavator architecture's per-core efficiency compensates entirely for the core-count deficit. Conversely, the Athlon's higher clock speeds do not give it an edge in single-threaded tests, indicating that the K10 architecture's single-thread performance is on par despite lower boost clocks.

The Verdict

The data does not support a performance-based recommendation for either processor. Both the AMD Athlon X4 845 and the AMD Opteron 3280 deliver identical benchmark results across all tested workloads, earning the same average score of 1106 and the same 31st percentile ranking. The Athlon X4 845 wins the head-to-head tally at 5 wins to 0, but every win is a tie with a deltaPct of 0, rendering the win count meaningless.

The selection between these two should be driven strictly by platform needs. The Athlon X4 845 offers a modern Excavator architecture on Socket FM2+, with an unlocked multiplier for overclocking and PCIe Gen 3 support. The Opteron 3280 provides eight cores and a large shared L3 cache on Socket AM3+, but its locked multiplier and older K10 architecture limit its flexibility. The Opteron 3280 has a launch MSRP of $229, which may be noted as a historical reference.

For users with an existing FM2+ motherboard, the Athlon X4 845 is the logical choice. For those on AM3+, the Opteron 3280 brings the same compute performance with additional cores that do not affect benchmarks but may be relevant for non-benchmarked workloads. The data shows that neither CPU outperforms the other, so the decision rests on socket compatibility and feature preferences rather than raw speed.

FAQ

Q: Which CPU has a higher average benchmark score, the Athlon X4 845 or the Opteron 3280?

A: Both have identical average benchmark scores of 1106, and both are ranked at the 31st percentile of all CPUs.

Q: Does the Opteron 3280's eight cores give it an advantage in multi-core tests?

A: No. In Cinebench R15 multicore, both CPUs score 324; in Cinebench R20 multicore, both score 1350; and in Cinebench R23 multicore, both score 3215. The core count difference does not translate into a benchmark advantage.

Q: What are the cache differences between the two processors?

A: The Athlon X4 845 has 320 KB of L1 and 2 MB of L2 cache, with no L3 cache. The Opteron 3280 has 384 KB of L1, 8 MB of L2, and 8 MB of shared L3 cache.

Q: Are the processors from the same generation?

A: No. The Athlon X4 845 is from the Athlon (Carrizo) generation, released in February 2016, while the Opteron 3280 is from the Opteron (Zurich) generation, released in March 2012.

Q: Which CPU supports overclocking?

A: The Athlon X4 845 has an unlocked multiplier, while the Opteron 3280 has a locked multiplier.

Q: How do these CPUs compare to their nearest rivals?

A: Both have an average score of 1106. The AMD Opteron 4280 and AMD PRO A12-8870 score 1107 (deltaPct -0.1), and the AMD PRO A12-9800 scores 1104 (deltaPct 0.2).