CPU Comparison

The Verdict

The benchmark data is unambiguous: the AMD Opteron 4226 wins every single head-to-head benchmark against the Intel Core i7-965, though the margins are razor-thin. Across five Cinebench tests, the Opteron 4226 takes all five wins, with deltas ranging from 0.1% to 0.6%. The average benchmark score tells the same story: the Opteron 4226 sits at 995, while the Core i7-965 sits at 993.

Despite being a server/workstation part with a lower base clock (2.70 GHz vs 3.20 GHz), the AMD Opteron 4226 edges out the Intel Core i7-965 in every measured workload. The Intel part does have a higher boost clock (3.47 GHz vs 3.10 GHz) and more threads (8 vs 6), but the AMD chip's newer 32nm process and larger L2 cache compensate. Both processors sit at the 27th percentile among all CPUs, indicating they are effectively peers in overall performance.

The verdict is straightforward: in this matchup, the AMD Opteron 4226 wins every benchmark, but the differences are so small (all under 1%) that real-world applications would see no perceptible difference. The Opteron 4226 is the nominal winner; the Core i7-965 is the better choice if you need an unlocked multiplier for overclocking or prefer a desktop-oriented platform. For pure benchmark scores, however, the data favors AMD in all five tests.

FAQ

Q: Which processor wins the most benchmarks in this head-to-head?

A: The AMD Opteron 4226 wins all five head-to-head benchmarks, including Cinebench R15 multicore (291 vs 290), R20 multicore (1213 vs 1212), R20 singlecore (171 vs 170), R23 multicore (2890 vs 2886), and R23 singlecore (408 vs 407).

Q: How large is the performance difference between these two CPUs?

A: The largest delta is in Cinebench R20 singlecore, where the AMD Opteron 4226 leads by 0.6%. The smallest margins are in R20 multicore and R23 multicore, both at 0.1%. Every benchmark shows less than a 1% difference.

Q: What are the core and thread counts for each processor?

A: The AMD Opteron 4226 has 6 cores and 6 threads. The Intel Core i7-965 has 4 cores and 8 threads, meaning Intel's chip has fewer physical cores but more threads thanks to Hyper-Threading.

Q: Do these processors support ECC memory?

A: Yes for AMD, no for Intel. The AMD Opteron 4226 supports ECC memory, while the Intel Core i7-965 does not.

Q: What is the memory channel configuration for each?

A: The AMD Opteron 4226 uses dual-channel DDR3 memory with 25.6 GB/s bandwidth. The Intel Core i7-965 uses triple-channel DDR3 memory, though its bandwidth figure is not listed.

Q: Are these processors still in production?

A: No. Both the AMD Opteron 4226 and the Intel Core i7-965 are marked as end-of-life production status.

Head-to-Head Benchmarks

The AMD Opteron 4226's clean sweep is notable but the margins tell the real story. In Cinebench R15 multicore, the Opteron 4226 scores 291 against the Core i7-965's 290, a 0.3% advantage. Moving to Cinebench R20 multicore, the AMD part scores 1213 versus 1212, a 0.1% edge. The same pattern repeats in Cinebench R23 multicore: 2890 vs 2886, another 0.1% win for AMD.

Single-core results follow the same trend. In Cinebench R20 singlecore, the Opteron 4226 posts 171 versus 170, the largest margin of any test at 0.6%. Cinebench R23 singlecore shows 408 vs 407, a 0.2% advantage for AMD. These scores suggest that despite the Intel part's higher clock speeds (3.20 GHz base, 3.47 GHz boost vs 2.70 GHz base, 3.10 GHz boost), the AMD chip's architecture efficiency keeps it marginally ahead in every workload.

The average benchmark scores confirm this near-parity: 995 for the Opteron 4226 and 993 for the Core i7-965. Both CPUs sit at the 27th percentile, and the nearest rivals for each include Intel's Core i7-960 at 993 (0% delta) and AMD's Phenom II X6 1065T at 993 (0% delta). The Opteron 4226's closest rival is the Intel Core i7-2635QM at 995 (0% delta), while the Core i7-965's nearest rival includes the Xeon W3565 at 993 (0% delta).

Specification Differences

The two processors diverge significantly on paper. The AMD Opteron 4226 offers 6 cores and 6 threads, while the Intel Core i7-965 has 4 cores and 8 threads. Clock speeds favor Intel: 3.20 GHz base and 3.47 GHz boost for the Core i7-965 versus 2.70 GHz base and 3.10 GHz boost for the Opteron 4226. Thermal design power also differs substantially: the Opteron 4226 draws 95W, while the Core i7-965 draws 130W.

Socket compatibility is entirely different: the AMD chip uses Socket C32, while the Intel chip uses Socket 1366. The AMD part supports ECC memory; the Intel part does not. Memory channels favor Intel's triple-channel configuration versus AMD's dual-channel, though AMD lists a specific bandwidth of 25.6 GB/s while Intel's figure is absent. The Opteron 4226 has a launch MSRP of $125; the Core i7-965 has no listed launch MSRP.

The Intel Core i7-965 has an unlocked multiplier; the AMD Opteron 4226 does not. Market segments differ: the Opteron 4226 targets server/workstation, while the Core i7-965 targets desktop. Cache configurations also differ: AMD has 288 KB L1, 6 MB L2, and 8 MB shared L3; Intel has 64 KB L1 per core, 256 KB L2 per core, and 8 MB shared L3.

Architecture Differences

The AMD Opteron 4226 uses the Bulldozer architecture on the Valencia codename, built on a 32 nm process at GlobalFoundries. It packs 1,200 million transistors on a 315 mm² die. The Intel Core i7-965 uses the older Nehalem architecture on the Bloomfield codename, built on a 45 nm process at Intel's own fabs. It contains 731 million transistors on a 263 mm² die.

The manufacturing process gap is significant: 32 nm versus 45 nm means AMD's transistors are physically smaller, which helps explain the Opteron's lower 95W TDP despite having more cores. The transistor count difference (1,200 million vs 731 million) reflects both the process advantage and the design philosophy difference. AMD's Bulldozer uses a modular design with shared resources, while Intel's Nehalem uses a more traditional per-core layout with dedicated L1 and L2 caches per core.

Cache hierarchies differ structurally. AMD allocates 288 KB L1 and 6 MB L2 across its 6 cores, with an 8 MB shared L3. Intel gives each of its 4 cores 64 KB L1 and 256 KB L2, also with an 8 MB shared L3. Both support DDR3 memory and PCIe Gen 2, and neither has integrated graphics. The market positioning is clear: AMD built the Opteron 4226 for servers with ECC support and a lower power envelope, while Intel built the Core i7-965 as an extreme desktop part with an unlocked multiplier.

Where Each One Wins

The AMD Opteron 4226 wins every benchmark in this comparison, but the context matters. Its 5-0 sweep includes wins in both single-core (R20: 171 vs 170, R23: 408 vs 407) and multi-core (R15: 291 vs 290, R20: 1213 vs 1212, R23: 2890 vs 2886) tests. For applications that rely heavily on Cinebench-style rendering workloads, the data shows the Opteron 4226 is consistently, if marginally, faster.

The Opteron 4226 also wins on efficiency and platform features. It draws 95W versus 130W for the Core i7-965, a meaningful difference for server environments. Its ECC memory support makes it suitable for error-sensitive workloads like database servers or scientific computing. The server/workstation market segment and Socket C32 platform indicate it belongs in multi-socket or rack-mounted systems.

The Intel Core i7-965, despite losing every benchmark, wins in specific usage scenarios. Its unlocked multiplier makes it the choice for overclocking enthusiasts, a capability the Opteron 4226 lacks. Its triple-channel memory configuration provides potentially higher memory bandwidth, though the specific figure is not listed. The desktop market segment and Socket 1366 platform suggest it was designed for high-end consumer builds, not datacenter racks.

For workloads where thread count matters more than raw per-core performance, the Core i7-965's 8 threads versus 6 could offer an advantage in heavily threaded applications that scale beyond 6 threads, the benchmark data does not capture this, as AMD wins all measured tests. Conversely, the Opteron 4226's 6 physical cores may handle certain server workloads more efficiently than Intel's 4 cores with Hyper-Threading.

The verdict from the data: if you are building a server or workstation with ECC requirements and power constraints, the AMD Opteron 4226 is the clear winner. If you are building an overclockable desktop system and can tolerate higher power draw, the Intel Core i7-965 offers the unlocked multiplier and triple-channel memory, but be aware it loses all benchmark comparisons in this dataset.