AMD Opteron 4274 HE vs Intel Core i7-3820 Comparison

The Intel Core i7-3820 and AMD Opteron 4274 HE are both end-of-life 32 nm parts from 2011-2012, but they target entirely different market segments: one is a desktop enthusiast chip, the other a low-power server processor. Despite their different designs—4 cores with Hyper-Threading versus 8 physical cores—their benchmark averages are nearly identical. The i7-3820 posts an average benchmark score of 1424, while the Opteron 4274 HE scores 1420, a delta of just 0.3%. Both sit at the 37th percentile among all CPUs. The real story is in how they achieve those scores, and what each platform offers around the silicon.

Head-to-Head Benchmarks

Looking at the six Cinebench results, the Intel Core i7-3820 wins every single test, but by margins so slim they are effectively ties. In Cinebench R15 multicore, the i7-3820 scores 496 against the Opteron’s 494, a 0.4% advantage. The single-core R15 result is a dead heat at 69 points for both. Moving to R20, the Intel chip again takes multicore with 2067 versus 2061 (0.3% delta), and single-core is again identical at 291 points. The pattern holds in R23: the i7-3820 leads multicore 4923 to 4909 (0.3%), and single-core 695 to 693 (0.3%).

The takeaways here are twofold. First, the 8-core Opteron’s extra physical cores do not translate into a multicore win against the 4-core/8-thread Intel part. The i7-3820’s higher base clock of 3.60 GHz and boost of 3.80 GHz, combined with Sandy Bridge’s superior per-core efficiency, compensate for having half the physical cores. Second, single-core performance is a wash—both chips score 69 in R15 and 291 in R20. This suggests the Opteron 4274 HE’s Bulldozer architecture, despite its lower 2.50 GHz base clock, can boost up to 3.50 GHz and keep pace in lightly threaded workloads.

The overall benchmark average tells the same story: 1424 for the i7-3820 versus 1420 for the Opteron. The i7-3820’s nearest rivals include the Intel Xeon Bronze 3106 (1422, +0.1%) and the Intel Core i7-3720QM (1421, +0.2%). The Opteron’s closest competitor is the Intel Core i7-2700K (1419, +0.1%). Neither chip has a decisive performance edge; the data shows a statistical tie across the board.

The Verdict

Strictly from the benchmark data, the Intel Core i7-3820 is the faster processor in every measured test, but the margins are negligible—never exceeding 0.4%. If you are choosing purely on Cinebench scores, the i7-3820 is the nominal winner, but the difference is within run-to-run variance. The Opteron 4274 HE, however, is not a desktop part; it is a Server/Workstation chip on AMD Socket C32. Its 65 W TDP is exactly half the i7-3820’s 130 W, making it the clear choice for power-constrained environments.

For a desktop builder, the i7-3820 offers a quad-channel DDR3 memory bus with 51.2 GB/s bandwidth, a 10 MB shared L3 cache, and 40 PCIe Gen 2 lanes from the CPU. The Opteron counter with dual-channel memory (25.6 GB/s), 8 MB L3, and ECC support. The i7-3820 also has an unlocked multiplier, which the Opteron lacks. The data says: if you need raw single-threaded speed and desktop flexibility, take the i7-3820. If you need a low-power, ECC-capable server chip that matches it in multicore, the Opteron is the practical pick.

Where Each One Wins

The Intel Core i7-3820 wins in raw performance across all six Cinebench tests, albeit by fractions of a percent. Its 3.60 GHz base and 3.80 GHz boost clocks are significantly higher than the Opteron’s 2.50 GHz base, though the Opteron closes the gap at 3.50 GHz boost. The i7-3820 also wins on platform features: quad-channel memory gives it 51.2 GB/s versus 25.6 GB/s, a full 2x bandwidth advantage. For workloads that are memory-bandwidth sensitive—such as large dataset manipulation or certain scientific compute—that difference matters more than the 0.3% Cinebench delta suggests.

The AMD Opteron 4274 HE wins on power efficiency. Its 65 W TDP is half the i7-3820’s 130 W. In a server rack with dozens of sockets, that translates to substantial thermal and electricity savings. It also supports ECC memory, a non-negotiable feature for data integrity in server environments. The Opteron has 8 physical cores versus the i7-3820’s 4 cores with 8 threads; in workloads that scale with physical cores rather than threads, the Opteron may hold up better over time, even though Cinebench shows them tied. The Opteron’s cache layout also differs—384 KB L1 and 8 MB L2—versus the Intel’s 64 KB L1 and 256 KB L2 per core.

FAQ

Q: Which CPU has better single-core performance?

A: They are identical. Both score 69 in Cinebench R15 single-core and 291 in R20 single-core. The i7-3820 edges ahead in R23 single-core with 695 versus 693, a 0.3% difference.

Q: Is the 8-core Opteron faster than the 4-core i7 in multicore workloads?

A: No. The i7-3820 wins every multicore test: R15 (496 vs 494), R20 (2067 vs 2061), and R23 (4923 vs 4909). The extra physical cores do not overcome the Intel’s clock speed advantage and architecture efficiency.

Q: Which chip supports ECC memory?

A: Only the AMD Opteron 4274 HE supports ECC memory. The Intel Core i7-3820 does not list ECC support in its specifications.

Q: What is the memory bandwidth difference?

A: The i7-3820 has a quad-channel DDR3 memory bus providing 51.2 GB/s. The Opteron 4274 HE has a dual-channel bus providing 25.6 GB/s—exactly half the bandwidth.

Q: Which CPU has a lower TDP?

A: The AMD Opteron 4274 HE has a 65 W TDP, which is half the Intel Core i7-3820’s 130 W TDP. This makes the Opteron substantially more power-efficient for dense server deployments.

Q: Are these CPUs still in production?

A: Both are end-of-life. The i7-3820 was released on February 12, 2012, and the Opteron 4274 HE was released on November 13, 2011.

Architecture Differences

The Intel Core i7-3820 uses Sandy Bridge-E architecture, codenamed Sandy Bridge-E, built on a 32 nm process by Intel. It contains 1,270 million transistors on a 294 mm² die. The design features 4 cores with 8 threads via Hyper-Threading, and a cache hierarchy of 64 KB L1 per core and 256 KB L2 per core, plus a 10 MB shared L3 cache. It supports DDR3 memory via a quad-channel bus and offers 40 PCIe Gen 2 lanes from the CPU.

The AMD Opteron 4274 HE uses Bulldozer architecture, codenamed Valencia, built on a 32 nm process by GlobalFoundries. It contains 1,200 million transistors on a 315 mm² die. The design features 8 physical cores (with 8 threads, no SMT), and a cache hierarchy of 384 KB L1, 8 MB L2, and 8 MB shared L3. It supports DDR3 via a dual-channel bus and offers PCIe Gen 2 connectivity. The Opteron also supports ECC memory, which the Intel part does not.

The fundamental architectural difference is core philosophy: Intel uses fewer, faster cores with SMT, while AMD uses more physical cores with a lower clock speed. The i7-3820’s base clock is 3.60 GHz versus the Opteron’s 2.50 GHz, but the Opteron boosts to 3.50 GHz, nearly matching the Intel’s 3.80 GHz boost. The transistor counts are very close (1,270M vs 1,200M), but Intel packs them into a slightly smaller die (294 mm² vs 315 mm²).

Specification Differences

The two processors differ in nearly every core specification. The Intel Core i7-3820 has 4 cores and 8 threads, while the AMD Opteron 4274 HE has 8 cores and 8 threads. Base clocks are 3.60 GHz versus 2.50 GHz, and boost clocks are 3.80 GHz versus 3.50 GHz. TDP is a major divider: 130 W for Intel, 65 W for AMD. The i7-3820 uses Intel Socket 2011, while the Opteron uses AMD Socket C32.

Memory support differs: both use DDR3, but the i7-3820 has a quad-channel bus (51.2 GB/s) versus the Opteron’s dual-channel bus (25.6 GB/s). ECC memory is supported only on the Opteron. PCIe connectivity is Gen 2 for both, but the i7-3820 provides 40 lanes from the CPU, while the Opteron’s lane count is unspecified. The i7-3820 has an unlocked multiplier; the Opteron does not. Cache sizes differ: the i7-3820 has 64 KB L1 and 256 KB L2 per core, with 10 MB shared L3; the Opteron has 384 KB L1, 8 MB L2, and 8 MB shared L3. The i7-3820’s launch MSRP was $305, and the Opteron’s was $377.