CPU Comparison

Head-to-Head Benchmarks

The benchmark data available for these two processors is asymmetrical, with the AMD Opteron 6276 having been subjected to the Cinebench R15, R20, and R23 test suites, while the AMD FX-8350 only carries Geekbench scores. Consequently, no direct head-to-head benchmark comparisons exist in the dataset. However, the aggregate average benchmark score provides a meaningful point of reference. The Opteron 6276 holds an average benchmark score of 1560, while the FX-8350 trails marginally at 1557, a difference of just three points. This places the Opteron 0.2% ahead of the FX-8350, a negligible margin that statistically represents a dead heat.

Looking at the nearest rival data for each processor further contextualizes this near-identical performance. The Opteron 6276 is listed with a 0.1% delta against the Intel Core i3-1115G4E (1559) and a -0.1% delta against the AMD Ryzen 3 1300X (1562). The FX-8350, for its part, shows a 0.2% delta against the Intel Core i3-9300 (1554) and a 0% delta against the Intel Xeon E3-1268L v5 (1557). The clustering of all these scores within a range of eight points (1554 to 1562) indicates that both AMD processors perform at essentially the same tier as several modern low-end and mid-range parts, despite their age and architectural differences.

Despite the lack of overlapping benchmark suites, the Opteron 6276's Cinebench results are instructive. Its R23 multi-core score of 5395 is roughly 2.4 times its single-core score of 761, showing strong scaling across its 16 cores. In contrast, the FX-8350's Geekbench multi-core score of 2551 is 4.5 times its single-core score of 563, which reflects the higher frequency of its eight cores but a much lower core count. The Opteron's single-core performance in R23 (761) is notably lower per-core than the FX-8350's Geekbench single-core result (563), but these are different benchmarks and cannot be directly compared. What the data does suggest is that the Opteron 6276 was designed for throughput-oriented workloads that exploit many threads, while the FX-8350 was tuned for lower-latency, higher-frequency desktop tasks.

FAQ

Q: Which processor has a higher average benchmark score?

A: The AMD Opteron 6276 has an average benchmark score of 1560, which is 0.2% higher than the AMD FX-8350's score of 1557. This places the Opteron ahead by a margin of only three points.

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

A: Both processors sit within a very tight performance cluster. The Opteron 6276 is 0.1% ahead of the Intel Core i3-1115G4E (1559) and 0.1% behind the AMD Ryzen 3 1300X (1562). The FX-8350 is exactly level with the Intel Xeon E3-1268L v5 (1557) and 0.2% ahead of the Intel Core i3-9300 (1554).

Q: What is the core and thread count difference?

A: The AMD Opteron 6276 features 16 cores and 16 threads, while the AMD FX-8350 features 8 cores and 8 threads. The Opteron has exactly double the core and thread count of the FX-8350.

Q: Which processor has a higher boost clock speed?

A: The AMD FX-8350 has a boost clock of 4.20 GHz, which is higher than the AMD Opteron 6276's boost clock of 3.20 GHz. The FX-8350 also has a higher base clock at 4.00 GHz compared to the Opteron's 2.30 GHz.

Q: Do both processors support ECC memory?

A: No. The AMD Opteron 6276 supports ECC memory, while the AMD FX-8350 does not. This is a key differentiator for server and workstation reliability requirements.

Q: What is the memory bandwidth for each processor?

A: The AMD Opteron 6276 has a quad-channel memory bus providing 51.2 GB/s of bandwidth. The AMD FX-8350 has a dual-channel memory bus providing 29.9 GB/s of bandwidth.

Architecture Differences

The architectural split between these two AMD parts is fundamental, despite both being built on the same 32 nm process node at GlobalFoundries. The Opteron 6276 uses the Bulldozer architecture under the Interlagos codename, while the FX-8350 uses the newer Piledriver architecture under the Vishera codename. This generational gap is significant: Piledriver was a refinement of Bulldozer, designed to improve instruction-level parallelism and branch prediction.

The die configuration highlights the server-oriented design of the Opteron. Its die size is listed as 2x 315 mm², indicating a dual-die module design, with a total transistor count of 2,400 million. The FX-8350, by contrast, uses a single 315 mm² die with 1,200 million transistors. This means the Opteron packs twice the silicon area and double the transistor budget, enabling its 16 cores and 16 threads. The FX-8350's 8 cores and 8 threads fit on half the silicon.

Cache hierarchies also differ substantially. The Opteron 6276 has 768 KB of L1 cache, 2 MB of L2 per module, and 8 MB of L3 per die. The FX-8350 has 384 KB of L1 cache, 8 MB of L2, and 8 MB of shared L3. The Opteron's L2 allocation of 2 MB per module reflects the Bulldozer design where two cores share a module, whereas the FX-8350's Piledriver design also uses a shared-module approach but lists an aggregate 8 MB L2. The L3 cache is effectively identical in size at 8 MB, though the Opteron's is per die, meaning across its dual-die setup it likely has a total of 16 MB of L3.

Memory architecture reinforces the Opteron's server pedigree. It supports quad-channel DDR3 memory with a theoretical bandwidth of 51.2 GB/s, and it supports ECC memory. The FX-8350 is limited to dual-channel DDR3 with 29.9 GB/s bandwidth, and it lacks ECC support. Both processors use PCIe Gen 2, but the Opteron is socketed in AMD Socket G34 while the FX-8350 uses AMD Socket AM3+. The FX-8350 also has an unlocked multiplier for overclocking, whereas the Opteron 6276 is locked.

The Verdict

The data presents a clear bifurcation in intended use cases. The AMD Opteron 6276 is a server and workstation processor, evidenced by its 16 cores, quad-channel ECC memory support, and 51.2 GB/s memory bandwidth. Its average benchmark score of 1560 is statistically tied with the FX-8350's 1557, but its architecture and feature set are tailored for multi-threaded, memory-intensive workloads where core count and memory throughput matter more than raw clock speed. Its 39th percentile ranking among all CPUs, shared by the FX-8350, indicates it is a mid-tier performer by modern standards, but its 16 threads give it a distinct advantage in parallel compute scenarios.

The AMD FX-8350, despite having half the cores and threads, matches the Opteron's aggregate performance. Its higher base clock of 4.00 GHz and boost clock of 4.20 GHz, combined with the Piledriver architecture's efficiency improvements, allow it to compete effectively in single-threaded and lightly threaded applications. Its desktop market segment, unlocked multiplier, and support for integrated graphics on certain motherboards make it a more flexible choice for general-purpose desktop computing. However, its dual-channel memory bus and lack of ECC support preclude it from serious server duty.

For users who need maximum parallel throughput, dense compute, or ECC memory for data integrity, the Opteron 6276 is the clear selection from the data. For users who prioritize high clock speeds, overclocking flexibility, and a desktop-oriented feature set, the FX-8350 is the appropriate pick. The near-identical average benchmark scores, with a delta of just 0.2%, mean that performance differences in real workloads will be determined more by the specific software's threading and memory patterns than by any intrinsic performance advantage of one chip over the other.

Specification Differences

| Specification | AMD Opteron 6276 | AMD FX-8350 |

|---|---|---|

| Series | Opteron 6000 series | null |

| Cores | 16 | 8 |

| Threads | 16 | 8 |

| Base Clock | 2.30 GHz | 4.00 GHz |

| Boost Clock | 3.20 GHz | 4.20 GHz |

| TDP | 115 W | 125 W |

| Socket | AMD Socket G34 | AMD Socket AM3+ |

| Architecture | Bulldozer | Piledriver |

| Codename | Interlagos | Vishera |

| Generation | Opteron (Interlagos) | FX (Vishera) |

| Transistors | 2,400 million | 1,200 million |

| Die Size | 2x 315 mm² | 315 mm² |

| L1 Cache | 768 KB | 384 KB |

| L2 Cache | 2 MB (per module) | 8 MB |

| L3 Cache | 8 MB (per die) | 8 MB (shared) |

| Memory Bus | Quad-channel | Dual-channel |

| Memory Bandwidth | 51.2 GB/s | 29.9 GB/s |

| ECC Memory | Yes | No |

| Integrated Graphics | null | On certain motherboards (Chipset feature) |

| Market Segment | Server/Workstation | Desktop |

| Release Date | 2011-11-13 | 2012-10-22 |

| Launch MSRP | $788 | $199 |

| Multiplier Unlocked | No | Yes |

| Part Number | OS6276WKTGGGU | FD8350FRW8KHKFD8350FRHKBOX |

The two processors share the same 32 nm process node, GlobalFoundries foundry, DDR3 memory support, PCIe Gen 2, and a 39th percentile ranking among all CPUs. Their average benchmark scores differ by only three points (1560 vs 1557), yet their specifications could hardly be more different in terms of core count, clock speeds, memory architecture, and intended market segment.