CPU Comparison

The AMD Opteron 3365 and Intel Core i5-2400 are both end-of-life processors from the early 2010s, but they target different segments: the Opteron is a server/workstation part on Socket AM3+, while the i5-2400 is a desktop chip on Socket 1155. The benchmark data shows a consistent, if narrow, margin of victory for the AMD part across all tested Cinebench workloads. The Opteron 3365 wins all five head-to-head tests, with its largest advantage being 6.1% in Cinebench R15 multicore and R23 multicore, and its smallest being 5.7% in Cinebench R20 single-core. The Intel i5-2400, despite having a higher base clock of 3.10 GHz versus 2.30 GHz, and a boost clock of 3.40 GHz versus 3.30 GHz, trails in every measured metric.

Head-to-Head Benchmarks

The head-to-head results are remarkably uniform, with the AMD Opteron 3365 winning each of the five Cinebench tests by a margin between 5.7% and 6.1%. In Cinebench R15 multicore, the Opteron scores 349 against the i5-2400's 329, a 6.1% delta. The same test pattern repeats in Cinebench R20 multicore, where the Opteron posts 1457 versus 1374, a 6% advantage. The single-core results are slightly tighter but still favor AMD: Cinebench R20 single-core shows 205 for the Opteron versus 194 for the i5-2400, a 5.7% gap, while Cinebench R23 single-core shows 489 versus 462, a 5.8% advantage. The largest absolute margin comes in Cinebench R23 multicore, where the Opteron scores 3470 against the i5-2400's 3272, again a 6.1% delta.

These results are interesting because they show that the Opteron's advantage is not simply a matter of core count. The Opteron has 8 cores and 8 threads, while the i5-2400 has 4 cores and 4 threads, yet the multicore wins are only around 6%. This suggests that the i5-2400's higher clocks, with a base of 3.10 GHz and boost of 3.40 GHz, partially compensate for its halved core count. In single-core tests, the Opteron still leads by roughly 5.7-5.8%, which is notable because the i5-2400's boost clock is 0.10 GHz higher. The Opteron's architecture appears to extract more instructions per clock in these workloads, despite running at lower frequencies.

The average benchmark scores put the Opteron at 1194, which places it in the 34th percentile of all CPUs, while the i5-2400 averages 1187, in the 33rd percentile. Both processors sit in the same performance tier, with the Opteron's nearest rivals including the AMD Athlon PRO 300U and Intel Core i3-4170 (both within 0.1%), while the i5-2400's nearest rivals include the Intel Core i5-4460T and AMD Opteron 6234 (within 0.2-0.3%). The overall percentile difference of one point is statistically minor, but the head-to-head data shows the Opteron is consistently ahead in every Cinebench test available.

The Verdict

From the data, the AMD Opteron 3365 is the clear winner for anyone running Cinebench-style multi-threaded and single-threaded workloads. It wins all five head-to-head tests, with margins ranging from 5.7% to 6.1%. The Intel Core i5-2400 does not win a single test in the comparison, so there is no benchmark-based argument for choosing it over the Opteron in this dataset. That said, the i5-2400 is not far behind; its scores are within 6% of the Opteron in every case, which means the two are in the same performance class.

The choice between them should be driven by platform and feature needs rather than raw performance. The Opteron 3365 is a server/workstation part with an 8-core design, while the i5-2400 is a desktop part with integrated graphics (Intel HD 2000). If the workload is heavily parallel and can use all 8 cores, the Opteron's slight edge in multicore tests (6.1% in R15 and R23) is the deciding factor. If the workload is single-threaded, the Opteron still leads, but by a smaller margin (5.7-5.8%). The i5-2400's only potential advantage in the data is its higher base and boost clocks, but those do not translate into a benchmark win.

For a system builder looking at these two end-of-life parts, the Opteron 3365 offers more cores and a small performance lead across the board. The i5-2400, however, has a lower transistor count (1,160 million versus 1,200 million) and a smaller die (216 mm² versus 315 mm²), which could imply lower manufacturing complexity, but the benchmark data does not reward that. The verdict is straightforward: the Opteron wins on every measured benchmark, so it is the better-performing CPU in this head-to-head.

Architecture Differences

The two processors are built on fundamentally different architectures. The AMD Opteron 3365 uses the K10 architecture with the codename "Delhi," produced on a 32 nm process at GlobalFoundries. It packs 1,200 million transistors on a 315 mm² die. The Intel Core i5-2400 uses the Sandy Bridge architecture, also on a 32 nm process, but fabricated by Intel, with 1,160 million transistors on a smaller 216 mm² die. Both are 32 nm parts, but the AMD design is larger in both transistor count and die size.

The core configurations differ significantly. The Opteron has 8 cores and 8 threads, meaning no simultaneous multithreading, while the i5-2400 has 4 cores and 4 threads, also without hyper-threading. The cache hierarchy is also different: the Opteron has 384 KB of L1 cache, 4 MB of L2 cache, and 8 MB of shared L3 cache. The i5-2400 has 64 KB of L1 per core (which totals 256 KB for four cores), 256 KB of L2 per core (totaling 1 MB), and 6 MB of shared L3 cache. The Opteron's larger caches, particularly the 8 MB L3, likely contribute to its consistent single-core advantage.

Memory support is DDR3 for both, with dual-channel buses. The Opteron lists a memory bandwidth of 29.9 GB/s, while the i5-2400 does not list a bandwidth figure in the data. The Opteron uses PCIe Gen 2, while the i5-2400 uses PCIe Gen 3 with 16 lanes from the CPU. The i5-2400 includes integrated graphics (Intel HD 2000), while the Opteron's graphics are listed as "on certain motherboards (chipset feature)," meaning it has no on-die GPU. The Opteron is a server/workstation part, while the i5-2400 is a desktop part.

Specification Differences

The two CPUs differ in several key specifications. The Opteron 3365 has 8 cores and 8 threads, while the i5-2400 has 4 cores and 4 threads. The base clock is 2.30 GHz for the Opteron versus 3.10 GHz for the i5-2400, and the boost clock is 3.30 GHz versus 3.40 GHz. The TDP is 65 watts for the Opteron and 95 watts for the i5-2400, meaning the AMD part draws less power despite having twice the cores. The sockets are incompatible: AMD Socket AM3+ for the Opteron and Intel Socket 1155 for the i5-2400.

Cache sizes differ: the Opteron has 384 KB of L1, 4 MB of L2, and 8 MB of shared L3, while the i5-2400 has 64 KB of L1 per core, 256 KB of L2 per core, and 6 MB of shared L3. The transistor counts are close (1,200 million versus 1,160 million), but the die sizes are not (315 mm² versus 216 mm²). The Opteron supports PCIe Gen 2, while the i5-2400 supports PCIe Gen 3 with 16 lanes. The memory bandwidth is listed as 29.9 GB/s for the Opteron but is absent for the i5-2400. The Opteron has no integrated graphics, while the i5-2400 includes Intel HD 2000. The market segments differ: Server/Workstation for AMD and Desktop for Intel. Finally, the part numbers are OS3365OLW8KHK for the Opteron and SR00Q for the i5-2400.

FAQ

Q: Which processor has a higher single-core score in Cinebench R23?

A: The AMD Opteron 3365 scores 489 in Cinebench R23 single-core, while the Intel Core i5-2400 scores 462, giving the Opteron a 5.8% advantage.

Q: What is the multicore performance difference in Cinebench R20?

A: The Opteron 3365 scores 1457, and the i5-2400 scores 1374, resulting in a 6% lead for the AMD part.

Q: Does the Intel Core i5-2400 have integrated graphics?

A: Yes, the i5-2400 includes Intel HD 2000 integrated graphics. The Opteron 3365 does not have on-die graphics; its display output depends on certain motherboards as a chipset feature.

Q: How many cores and threads does each CPU have?

A: The AMD Opteron 3365 has 8 cores and 8 threads. The Intel Core i5-2400 has 4 cores and 4 threads.

Q: Which CPU has a higher TDP?

A: The Intel Core i5-2400 has a TDP of 95 watts, while the AMD Opteron 3365 has a TDP of 65 watts.

Q: What are the memory bandwidth figures for the Opteron 3365?

A: The Opteron 3365 lists a memory bandwidth of 29.9 GB/s with dual-channel DDR3 support. The i5-2400 does not have a bandwidth figure listed.

Where Each One Wins

The AMD Opteron 3365 wins in every benchmark category recorded in the head-to-head data. In multi-threaded workloads, it leads by 6.1% in Cinebench R15 multicore (349 versus 329) and 6% in Cinebench R20 multicore (1457 versus 1374). Its advantage extends to single-threaded tests as well, with a 5.7% lead in Cinebench R20 single-core (205 versus 194) and a 5.8% lead in Cinebench R23 single-core (489 versus 462). The Opteron also has a higher average benchmark score of 1194 versus 1187, and a higher percentile ranking of 34 versus 33.

The Intel Core i5-2400 does not win any of the five head-to-head tests. However, it has higher clock speeds (3.10 GHz base versus 2.30 GHz, and 3.40 GHz boost versus 3.30 GHz), which may be relevant for workloads not captured in the Cinebench suite, though no such benchmark data is provided. The i5-2400 also has integrated graphics, which is a feature the Opteron lacks, making it suitable for systems that require a display output without a discrete GPU. Its PCIe Gen 3 support (16 lanes) is newer than the Opteron's PCIe Gen 2.

For multi-core rendering tasks, the Opteron is the pick, as it wins all multicore tests. For single-core tasks, the Opteron also wins, making it the overall performance choice. The i5-2400's only advantages are its integrated GPU and higher clocks, which do not translate into any benchmark win in this dataset. If a system requires integrated graphics or a desktop platform, the i5-2400 is the only option of the two, but for raw CPU compute, the Opteron 3365 is superior in every tested metric.