CPU Comparison

The AMD Opteron 4226 and Intel Core i5-2500S are two end-of-life processors from 2011 that, despite their different market segments, deliver nearly identical benchmark scores. The data shows the AMD Opteron 4226 wins all five head-to-head Cinebench tests, but by margins of 0.7% to 1.2%, effectively a statistical tie. Both CPUs sit at the 27th percentile of all CPUs, with the Opteron averaging 995 and the i5-2500S averaging 1004. The Opteron is the server/workstation part, while the i5-2500S is a desktop chip with integrated graphics. Neither chip offers a meaningful performance advantage in the metrics provided.

The Verdict

The benchmark data tells a story of near-perfect parity. The AMD Opteron 4226 wins every single head-to-head comparison, but the largest margin is just 1.2% in Cinebench R20 single-core (171 vs 169). Across the five shared tests, the Opteron leads by 0.7% to 1.0% in multi-core workloads and 1.0% to 1.2% in single-core workloads. These deltas are within run-to-run variance; no user would perceive a difference in real-world applications.

For server and workstation deployments, the Opteron 4226 is the logical choice because it supports ECC memory, which the i5-2500S does not. The Opteron also offers more physical cores (6 vs 4) and a larger shared L3 cache (8 MB vs 6 MB), which can matter in multi-threaded server workloads, even if the Cinebench scores don't reflect a large advantage. Its launch MSRP was $125.

For desktop use, the i5-2500S holds the edge in platform features. It includes Intel HD 2000 integrated graphics, which the Opteron lacks entirely, and supports PCIe Gen 3 with 16 CPU lanes compared to the Opteron's Gen 2. The i5-2500S also has a higher boost clock (3.70 GHz vs 3.10 GHz) and a lower TDP (65 W vs 95 W), making it the more efficient and flexible choice for a desktop build.

The verdict is clear: if you need ECC memory and more cores in a server context, choose the Opteron 4226. If you need integrated graphics, lower power draw, and newer PCIe support in a desktop, choose the i5-2500S. On pure CPU compute performance, the data shows no winner.

Architecture Differences

The two chips come from fundamentally different design philosophies. The AMD Opteron 4226 is built on the Bulldozer architecture, codenamed Valencia, and fabricated by GlobalFoundries on a 32 nm process. It packs 1,200 million transistors into a 315 mm² die. The chip features 6 cores and 6 threads, with a base clock of 2.70 GHz and a boost clock of 3.10 GHz. Its cache hierarchy includes 288 KB of L1, 6 MB of L2, and 8 MB of shared L3. The Opteron supports DDR3 memory on a dual-channel bus with 25.6 GB/s of bandwidth and includes ECC memory support. It uses the AMD Socket C32 and has a TDP of 95 W.

The Intel Core i5-2500S is built on the Sandy Bridge architecture, fabricated by Intel on the same 32 nm process. It contains 1,160 million transistors on a 216 mm² die, significantly smaller than the Opteron. The chip has 4 cores and 4 threads, with a base clock of 2.70 GHz and a boost clock of 3.70 GHz. Its cache is organized per-core: 64 KB of L1 per core, 256 KB of L2 per core, and 6 MB of shared L3. The i5-2500S supports DDR3 on a dual-channel bus, but the fact pack does not list its memory bandwidth. It does not support ECC memory. The chip uses Intel Socket 1155 and includes Intel HD 2000 integrated graphics. It supports PCIe Gen 3 with 16 CPU-only lanes, a generation ahead of the Opteron's Gen 2. Its TDP is 65 W, significantly lower than the Opteron's 95 W.

The transistor counts are remarkably close (1,200 million vs 1,160 million), but the die sizes differ dramatically (315 mm² vs 216 mm²), indicating the Bulldozer design was less dense than Sandy Bridge. The i5-2500S achieves a higher boost clock (3.70 vs 3.10 GHz) with fewer cores and a lower TDP. The Opteron counters with two extra cores and 2 MB more shared L3 cache.

Where Each One Wins

The Opteron 4226 wins in server-oriented attributes. It offers ECC memory support, which is critical for data integrity in server and workstation environments. It has 6 cores versus 4, giving it more physical parallelism for heavily threaded server workloads. Its 8 MB shared L3 cache is 33% larger than the i5-2500S's 6 MB. In the head-to-head benchmarks, the Opteron wins all five Cinebench tests, including multi-core runs where its extra cores should theoretically help. The largest victory is a 1.2% lead in Cinebench R20 single-core, despite having a lower boost clock, this suggests the Bulldozer architecture was competitive on a per-clock basis in these specific tests.

The i5-2500S wins in desktop-centric features. It includes Intel HD 2000 integrated graphics, eliminating the need for a separate GPU in basic desktop systems. It supports PCIe Gen 3 with 16 lanes, providing double the bandwidth of the Opteron's Gen 2 for compatible expansion cards. Its 65 W TDP is 31% lower than the Opteron's 95 W, making it easier to cool and more energy-efficient. The i5-2500S also has a higher boost clock (3.70 vs 3.10 GHz), which can benefit lightly threaded applications that rely on single-core speed. Its average benchmark score of 1004 is slightly higher than the Opteron's 995, though the difference is negligible.

FAQ

Q: Which processor has more cores?

A: The AMD Opteron 4226 has 6 cores and 6 threads, while the Intel Core i5-2500S has 4 cores and 4 threads.

Q: Does either chip support ECC memory?

A: Yes, the AMD Opteron 4226 supports ECC memory. The Intel Core i5-2500S does not.

Q: Which CPU includes integrated graphics?

A: The Intel Core i5-2500S includes Intel HD 2000 integrated graphics. The AMD Opteron 4226 has no integrated graphics.

Q: How close are the benchmark scores between the two?

A: The Opteron 4226 wins all five head-to-head Cinebench tests, but by margins of only 0.7% to 1.2%. Their average benchmark scores are 995 for the Opteron and 1004 for the i5-2500S.

Q: Which chip has a lower power draw?

A: The Intel Core i5-2500S has a TDP of 65 W, compared to the AMD Opteron 4226's 95 W.

Q: What PCIe generation does each support?

A: The AMD Opteron 4226 supports PCIe Gen 2. The Intel Core i5-2500S supports PCIe Gen 3 with 16 CPU-only lanes.

Head-to-Head Benchmarks

The head-to-head results show an unbroken string of wins for the AMD Opteron 4226, though every margin is razor-thin. In Cinebench R15 multi-core, the Opteron scores 291 against the i5-2500S's 288, a 1% advantage. Cinebench R20 multi-core shows a similar pattern: 1213 vs 1204, a 0.7% lead. The single-core tests follow the same trend. Cinebench R20 single-core gives the Opteron 171 points against 169 for the Intel chip, a 1.2% lead, the largest margin in any test. Cinebench R23 multi-core sees the Opteron at 2890 versus 2867, a 0.8% difference. Cinebench R23 single-core closes the set with 408 against 404, another 1% win.

The fact that the Opteron wins single-core tests despite having a 0.60 GHz lower boost clock is notable. It suggests that in these specific Cinebench workloads, the Bulldozer core design was competitive with Sandy Bridge on a per-thread basis. The multi-core results are more surprising: the Opteron only leads by 0.7% to 1.0% despite having 50% more cores. This indicates that Cinebench's scaling on the Opteron was poor, or that the i5-2500S's higher boost clock compensated for its two fewer cores.

The i5-2500S has two additional benchmarks not shared with the Opteron: Geekbench multi-core at 1511 and Geekbench single-core at 582. These scores are not comparable to the Cinebench results, but they provide additional context for the Intel chip's performance. The i5-2500S also has a slightly higher average benchmark score (1004 vs 995) across all tests, even though it loses every head-to-head comparison. This is because the Geekbench results pull its average up, while the Opteron's average is based solely on its Cinebench scores.

In the nearest rival comparisons, both chips are clustered tightly with similar-performance CPUs. The Opteron 4226 matches the Intel Core i7-2635QM and Intel Core i7-2920XM exactly (995 avg score, 0% delta), and sits just ahead of the Intel Core i3-8130U (994, 0.1%) and Intel Xeon W3565 (993, 0.2%). The i5-2500S is exactly matched with the Intel Core i5-4300M (1004, 0%), and trails the Intel Core i7-5600U and Intel Core i7-2630QM by 0.1% (both at 1005) and the AMD FX-9830P by 0.2% (1006). These rankings reinforce that both CPUs are firmly in the mid-range of 2011-era performance, with no significant advantage either way.