AMD Opteron 6328 vs Intel Core i5-2500K Comparison

Where Each One Wins

The recorded benchmark data splits cleanly along workload type, but not in the way one might expect from the core counts alone. The AMD Opteron 6328 wins every single head-to-head benchmark in the database, across both multi-core and single-core Cinebench tests. That is five wins out of five recorded comparisons. The Intel Core i5-2500K does not register a single victory in any measured test.

The Opteron 6328’s advantage is consistent, not sporadic. In multi-core workloads, it leads by roughly 22% across all three Cinebench versions (R15, R20, and R23). The same margin appears in single-core tests, where the Opteron also leads by about 22%. This uniformity suggests a structural performance edge rather than a workload-specific quirk.

For the Intel Core i5-2500K, the story is one of consistent but narrow defeat. Its scores trail the Opteron by between 21.9% and 22.1% in every recorded comparison. The tight spread of these deltas, all within 0.2 percentage points of each other, indicates that the performance gap is stable across rendering tasks regardless of the Cinebench version used.

The use-case split is therefore straightforward from the data: the AMD part dominates in every benchmark category where both were measured. Users seeking higher Cinebench scores, whether single-threaded or multi-threaded, would find the Opteron 6328 preferable. The Intel part’s role is limited to scenarios where its platform characteristics, such as integrated graphics or desktop socket, matter more than raw benchmark output.

FAQ

Q: Which CPU has the higher average benchmark score?

A: The Intel Core i5-2500K has an average benchmark score of 1329, while the AMD Opteron 6328 scores 1304. The Intel part leads by 25 points in this aggregate metric, despite losing every individual head-to-head test.

Q: How large is the Opteron’s lead in Cinebench R23 multi-core?

A: The Opteron 6328 scores 4510 against the i5-2500K’s 3523, a difference of 987 points. The delta percentage is 21.9% in favor of AMD.

Q: Does the Opteron also win single-core tests?

A: Yes. In Cinebench R23 single-core, the Opteron scores 636 versus 497 for the i5-2500K, a 21.9% advantage. The same pattern holds in R20 single-core, where AMD leads 267 to 208, a 22.1% gap.

Q: Are both CPUs in the same performance percentile?

A: Both processors sit at the 35th percentile against all CPUs in the database. Their average benchmark scores differ by only 25 points, placing them in essentially the same performance tier.

Q: What are the nearest rivals for each CPU?

A: For the i5-2500K, the nearest rival is the Intel Core i5-4460S with an average score of 1330, a delta of -0.1%. For the Opteron 6328, the nearest rival is the Intel Core i5-6400 at 1307, a delta of -0.2%.

Q: Which CPU supports ECC memory?

A: The AMD Opteron 6328 supports ECC memory. The Intel Core i5-2500K does not.

Head-to-Head Benchmarks

The head-to-head data shows a decisive sweep for the AMD Opteron 6328 across all five recorded Cinebench tests. The smallest margin is in Cinebench R20 single-core, where AMD leads by 22.1%. Every other test shows a 21.9% gap, with the sole exception of Cinebench R15 multi-core, which also sits at 22%.

Starting with Cinebench R15 multi-core, the Opteron records 454 points against 354 for the i5-2500K. The 100-point difference translates to a 22% advantage. This is the largest absolute gap in the dataset, though the percentage delta is consistent with the other tests.

Moving to Cinebench R20 multi-core, the Opteron scores 1894 versus 1479 for Intel. The 415-point margin is again 21.9%. In single-core R20, the Opteron posts 267 against 208, a 59-point lead that works out to 22.1%.

Cinebench R23 multi-core shows the Opteron at 4510 versus 3523, a 987-point difference. The percentage delta remains 21.9%. In R23 single-core, the Opteron scores 636 against 497, a 139-point lead, also at 21.9%.

The consistency of these deltas is remarkable. Across five tests spanning three different Cinebench versions and both single and multi-threaded workloads, the Opteron’s advantage never deviates outside the 21.9% to 22.1% range. This points to a fundamental per-clock or per-core efficiency difference rather than a workload-specific advantage.

For the i5-2500K, the nearest rivals in the database include the Intel Core i5-4460S with a delta of -0.1% and the Intel Core i5-760 at -0.6%. The Opteron’s nearest rivals include the Intel Core i5-6400 at -0.2% and the Intel Core i7-3610QE at 0.5%. These rival comparisons confirm that both CPUs sit in a crowded mid-range tier, but the Opteron holds a clear edge within that tier.

Specification Differences

The two processors differ across nearly every major specification category. The Intel Core i5-2500K uses 4 cores and 4 threads, while the AMD Opteron 6328 doubles that to 8 cores and 8 threads. Base clocks are close: 3.30 GHz for Intel versus 3.20 GHz for AMD. Boost clocks favor AMD slightly, 3.80 GHz versus 3.70 GHz.

Thermal design power differs substantially. The i5-2500K is rated at 95 watts, while the Opteron 6328 draws 115 watts. Sockets are incompatible: Intel uses Socket 1155, AMD uses Socket G34. The Intel part features an unlocked multiplier, the AMD part does not.

Memory support shows a clear platform divide. Both support DDR3, but the Intel part runs dual-channel with 25.6 GB/s bandwidth, while the AMD part runs quad-channel with 59.7 GB/s. ECC memory is supported only on the Opteron. PCIe generation is Gen 2 for both, but the Intel part specifies 16 lanes (CPU only), while the AMD part simply lists Gen 2 without lane details.

Integrated graphics are present only on the Intel part, which includes Intel HD 3000. The Opteron has no integrated graphics. Market segments differ accordingly: desktop for Intel, server/workstation for AMD. Release dates are separated by nearly two years, with Intel launching in January 2011 and AMD in November 2012.

The launch MSRP for the i5-2500K was $216. The Opteron 6328 launched at a higher price point, though the exact figure is noted in the database.

Architecture Differences

The architectural split is fundamental. The Intel Core i5-2500K uses Sandy Bridge architecture, built on a 32 nm process by Intel’s own foundry. The AMD Opteron 6328 uses Piledriver architecture, codenamed Abu Dhabi, also on a 32 nm process but manufactured by GlobalFoundries.

Transistor counts diverge sharply. The Intel die packs 1,160 million transistors on a 216 mm² die. The AMD part uses 2,400 million transistors spread across two 315 mm² dies, for a combined die area of 630 mm². This dual-die design explains the Opteron’s larger physical footprint and higher power draw.

Cache hierarchies differ in structure. The Intel part provides 64 KB of L1 per core and 256 KB of L2 per core, with 6 MB of shared L3. The AMD part provides 384 KB of total L1, 2 MB of L2 per module, and 8 MB of L3 per die. With two dies, the Opteron effectively offers 16 MB of total L3, though the database lists the per-die figure.

The core count advantage for AMD comes with a modular design. Piledriver uses modules that share resources, which explains why 8 cores deliver only a 22% multi-core advantage over 4 Intel cores rather than a 100% advantage. The single-core results reinforce this: despite a higher boost clock, the Opteron’s per-thread performance in Cinebench R23 single-core (636) is only 21.9% ahead of the i5-2500K (497), not the 40% or more one might expect from a newer architecture.

Memory bandwidth is a major architectural differentiator. The Opteron’s quad-channel DDR3 interface delivers 59.7 GB/s, more than double the i5-2500K’s 25.6 GB/s. This bandwidth advantage likely benefits server workloads, though the Cinebench tests in the database do not specifically measure memory-bound tasks.

The Verdict

The data supports a clear choice for users prioritizing Cinebench performance: the AMD Opteron 6328 wins every recorded benchmark by a consistent margin of approximately 22%. Its 8 cores and 8 threads, combined with a higher boost clock and quad-channel memory, deliver superior scores across all five head-to-head tests. The Opteron’s nearest rival, the Intel Core i5-6400, sits just 0.2% behind its average score, placing it in the same performance tier as modern mid-range parts.

The Intel Core i5-2500K is not without merit. Its average benchmark score of 1329 actually exceeds the Opteron’s 1304, and it ties at the 35th percentile. The Intel part offers integrated graphics, a lower 95-watt TDP, and an unlocked multiplier for overclocking. Its nearest rival, the Intel Core i5-4460S, is only 0.1% behind, indicating the i5-2500K remains competitive with much newer silicon.

For desktop users who need integrated graphics, a compact Socket 1155 platform, or an unlocked multiplier, the i5-2500K is the sensible choice. For server or workstation deployments where ECC memory, quad-channel bandwidth, and raw multi-threaded rendering performance matter, the Opteron 6328 dominates. The 22% lead in every Cinebench test is the decisive factor; no measured workload in the database favors the Intel part.

The final recommendation depends on platform requirements. If the task is Cinebench-style rendering and the platform can accommodate a 115-watt Socket G34 processor, the Opteron 6328 is the stronger performer in every recorded metric. If the task involves desktop features, lower power consumption, or overclocking, the i5-2500K’s specifications make it the more appropriate part, despite its benchmark deficit.