CPU Comparison

The Intel Xeon X5550 and AMD PRO A8-8650B are both end-of-life processors that land in the same performance tier, with average benchmark scores of 888 and 887 respectively. The data shows a remarkably close contest, yet the AMD part sweeps every head-to-head benchmark in this comparison, despite the Intel chip’s higher thread count and server-grade pedigree.

Head-to-Head Benchmarks

The AMD PRO A8-8650B wins all five shared benchmark tests, with margins that are consistent but narrow. In Cinebench R15 multi-core, the AMD scores 275 against the Intel’s 259, a 5.8% advantage. That pattern repeats in Cinebench R20 multi-core, where AMD posts 1148 versus 1083, a 5.7% lead. The R23 multi-core test shows 2734 for AMD and 2580 for Intel, again a 5.6% gap. These results indicate that despite having only four threads to the Intel’s eight, the AMD’s higher clock speeds compensate effectively in heavily threaded workloads.

Single-core performance tells the same story. The AMD PRO A8-8650B scores 162 in Cinebench R20 single-core, beating the Xeon’s 152 by 6.2%. In R23 single-core, AMD’s 386 tops Intel’s 364 by 5.7%. The largest relative win for AMD comes in the R20 single-core test, where the delta reaches 6.2%. This is notable because the Xeon’s extra threads offer no benefit in single-threaded tasks, and the AMD’s superior base and boost clocks, 3.20 GHz and 3.90 GHz versus 2.67 GHz and 3.07 GHz, drive the advantage.

The overall benchmark picture places both processors at the 24th percentile among all CPUs. The Xeon’s average score of 888 edges out the AMD’s 887 by a single point, though the nearestRivals data shows the AMD at a -0.1% delta relative to the Xeon. In practical terms, these are equivalent performers, but the AMD wins every direct comparison in this dataset. The Xeon’s best showing is a tie with the Intel Core i3-6100 at 888 average score, while the AMD matches the Intel Pentium G4560T at 887. Both chips sit within 0.2% of each other and of the Intel Core i7-860, making this a four-way statistical dead heat in the broader market.

Architecture Differences

The two processors come from different eras and design philosophies. The Intel Xeon X5550 uses the Nehalem architecture on the Gainestown codename, built on a 45 nm process at Intel’s foundry. It packs 731 million transistors into a 263 mm² die. The AMD PRO A8-8650B uses the Steamroller architecture on the Godaveri codename, fabricated by GlobalFoundries on a 28 nm process. That newer node allows 2,411 million transistors in a slightly smaller 245 mm² die. The AMD’s transistor count is more than three times higher, a direct result of the denser manufacturing process.

Core and cache layouts differ significantly. The Xeon offers 4 cores with 8 threads via Hyper-Threading, while the AMD provides 4 cores and 4 threads with no simultaneous multithreading. The Intel chip has a three-level cache hierarchy: 64 KB L1 per core, 256 KB L2 per core, and 8 MB shared L3. The AMD uses a two-level design: 256 KB total L1 and 4 MB total L2, with no L3 cache at all. This means the Xeon has a larger aggregate cache pool, but the AMD’s cache is physically closer to the cores in a simpler hierarchy.

Memory support also diverges. Both support DDR3, but the Xeon uses a triple-channel memory bus while the AMD uses dual-channel. The AMD’s memory bandwidth is listed at 34.1 GB/s, a figure the Xeon’s fact sheet does not provide. The Xeon supports ECC memory, which is typical for its server/workstation market segment. The AMD does not support ECC, reflecting its desktop positioning. PCIe generations differ as well: the Xeon offers Gen 2, while the AMD provides Gen 3 with 16 lanes on the CPU only.

The most conspicuous difference is integrated graphics. The AMD PRO A8-8650B includes a Radeon R7 iGPU, making it an accelerated processing unit in the truest sense. The Intel Xeon X5550 has no integrated graphics whatsoever, which is standard for a server part. The AMD’s TDP is 65 watts, substantially lower than the Xeon’s 95 watts, despite the AMD having higher clock speeds and a built-in GPU. The Xeon’s socket is Intel Socket 1366, while the AMD uses AMD Socket FM2+. Neither chip has an unlocked multiplier.

Where Each One Wins

Given that the AMD wins all five head-to-head benchmarks, the use-case split is heavily skewed. The AMD PRO A8-8650B is the better choice for any workload represented in this dataset. In multi-threaded rendering tasks like Cinebench R15, R20, and R23, the AMD leads by 5.6% to 5.8%. This is counterintuitive given the Xeon’s 8-thread capability, but the AMD’s higher clocks and newer architecture overcome the thread deficit. For single-threaded tasks, the AMD’s advantage ranges from 5.7% to 6.2%, again driven by its clock speed superiority.

The Xeon’s theoretical strengths do not translate into wins here. Its 8 MB L3 cache and triple-channel memory interface are not reflected in benchmark superiority, likely because the Cinebench suite does not heavily stress those subsystems. The Xeon’s ECC memory support and server market segment make it suited for reliability-focused environments, but those features are not benchmarkable in this dataset. The AMD, with its Radeon R7 integrated graphics, offers a complete desktop solution where no discrete GPU is required, a capability the Xeon simply lacks.

For a system builder choosing between these two, the data is unambiguous. The AMD PRO A8-8650B wins every measured test, consumes less power on paper, and includes integrated graphics. The Xeon’s only advantages are ECC support, a larger L3 cache, and more threads, none of which produce a benchmark victory in this comparison. The AMD’s 3.90 GHz boost clock versus the Xeon’s 3.07 GHz appears to be the decisive factor across all five tests.

FAQ

Q: Which processor has a higher average benchmark score?

A: The Intel Xeon X5550 has an average benchmark score of 888, while the AMD PRO A8-8650B scores 887. The difference is one point, or approximately 0.1%.

Q: How much faster is the AMD PRO A8-8650B in multi-core rendering?

A: In Cinebench R23 multi-core, the AMD scores 2734 versus the Intel’s 2580, a 5.6% advantage. The R20 multi-core test shows a 5.7% lead (1148 vs 1083), and the R15 test shows a 5.8% lead (275 vs 259).

Q: Does the Xeon’s 8-thread capability help it win any benchmarks?

A: No. Despite having 8 threads versus the AMD’s 4, the Xeon loses all five shared benchmarks. The AMD wins multi-core tests by 5.6% to 5.8%, indicating its higher clock speeds compensate for the thread deficit.

Q: What is the difference in single-core performance?

A: The AMD leads in both single-core tests. In Cinebench R20 single-core, AMD scores 162 versus Intel’s 152, a 6.2% gap. In R23 single-core, AMD scores 386 versus Intel’s 364, a 5.7% gap.

Q: Do these processors support the same memory features?

A: Both support DDR3, but the Xeon uses triple-channel memory while the AMD uses dual-channel. The AMD has a listed memory bandwidth of 34.1 GB/s. The Xeon supports ECC memory; the AMD does not.

Q: Which processor includes integrated graphics?

A: Only the AMD PRO A8-8650B includes integrated graphics, a Radeon R7. The Intel Xeon X5550 has no integrated graphics, consistent with its server/workstation market segment.

Specification Differences

| Specification | Intel Xeon X5550 | AMD PRO A8-8650B |

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

| Threads | 8 | 4 |

| Base Clock | 2.67 GHz | 3.20 GHz |

| Boost Clock | 3.07 GHz | 3.90 GHz |

| TDP | 95 W | 65 W |

| Socket | Intel Socket 1366 | AMD Socket FM2+ |

| Architecture | Nehalem | Steamroller |

| Codename | Gainestown | Godaveri |

| Process Node | 45 nm | 28 nm |

| Foundry | Intel | GlobalFoundries |

| Transistors | 731 million | 2,411 million |

| Die Size | 263 mm² | 245 mm² |

| L1 Cache | 64 KB (per core) | 256 KB |

| L2 Cache | 256 KB (per core) | 4 MB |

| L3 Cache | 8 MB (shared) | None |

| Memory Bus | Triple-channel | Dual-channel |

| Memory Bandwidth | Not specified | 34.1 GB/s |

| ECC Memory | Yes | No |

| PCIe | Gen 2 | Gen 3, 16 Lanes (CPU only) |

| Integrated Graphics | None | Radeon R7 |

| Market Segment | Server/Workstation | Desktop |

| Release Date | 2009-03-29 | 2015-09-28 |

| Part Number | SLBF5 | AD865BYBI44JC |