AMD Opteron 6238 vs Intel Core i7-3820QM Comparison

The Verdict

The recorded data paints a remarkably close picture between the AMD Opteron 6238 and the Intel Core i7-3820QM. Across the six shared Cinebench tests, the Opteron 6238 wins all six, but by margins that are almost imperceptible. In the R15 multicore test, both processors score exactly 481. In R20 multicore, the Opteron leads by a 0.1% delta (2008 vs. 2006). In R23 multicore, the Opteron again leads by 0.1% (4781 vs. 4777). Single-core tests show identical scores of 67 in R15 and 283 in R20, with the Opteron ahead by 0.1% in R23 single-core (675 vs. 674).

The database places both chips at the 36th percentile among all CPUs. The Opteron 6238 has an average benchmark score of 1383, while the Core i7-3820QM sits at 1366. That is a 1.2% difference in aggregate, a negligible gap for most workloads.

Who should pick which? The data shows the Opteron 6238 is the nominal winner in every head-to-head test, but the margins are so small that the decision should rest on platform and feature needs, not raw performance. The Opteron is a 12-core, 12-thread server processor with a 115 W TDP, quad-channel DDR3 memory support, ECC memory, and a PCIe Gen 2 interface. The Core i7-3820QM is a 4-core, 8-thread mobile chip with a 45 W TDP, dual-channel memory, no ECC support, and integrated Intel HD 4000 graphics. If the workload requires ECC memory or a server-class socket with quad-channel bandwidth, the Opteron 6238 is the clear choice. If the application is mobile, power-constrained, or needs integrated graphics, the Core i7-3820QM is the practical option despite losing the benchmark sweep.

Architecture Differences

The two processors come from fundamentally different design philosophies. The AMD Opteron 6238 uses the Bulldozer architecture, codenamed Interlagos, and belongs to the Opteron 6000 series. It is built on a 32 nm process at GlobalFoundries, with 2,400 million transistors spread across a dual-die design measuring 2x 315 mm². The Intel Core i7-3820QM uses the Ivy Bridge architecture, also codenamed Ivy Bridge, built on a 22 nm process at Intel, with 1,400 million transistors on a single 160 mm² die.

Core counts differ sharply. The Opteron 6238 packs 12 cores and 12 threads, while the Core i7-3820QM has 4 cores and 8 threads thanks to Hyper-Threading. The Opteron's cache layout is unusual: 768 KB of L1, 2 MB of L2 per module, and 8 MB of L3 per die. The Core i7 has 64 KB of L1 per core, 256 KB of L2 per core, and 8 MB of shared L3 cache. Both have 8 MB of total L3, but the Opteron's is split across two dies, while Intel's is shared across all four cores.

Memory support also diverges. The Opteron 6238 supports DDR3 memory over a quad-channel bus with a peak bandwidth of 51.2 GB/s, and it supports ECC memory. The Core i7-3820QM uses dual-channel DDR3, has no ECC support, and the database does not list a memory bandwidth figure for it. The Opteron is a server/workstation part with a PCIe Gen 2 interface, while the Core i7 is a mobile processor with integrated Intel HD 4000 graphics. The Opteron has no integrated graphics. Clock speeds favor Intel: the Core i7 has a 2.70 GHz base clock and 3.70 GHz boost, versus 2.60 GHz base and 3.20 GHz boost for the Opteron. The Opteron has a higher TDP at 115 W, while the Core i7 draws 45 W.

The release dates are close, with the Opteron launching on 2011-11-13 and the Core i7 on 2012-04-28. The Opteron carries a launch MSRP of $455, while the Core i7 has no listed launch MSRP. Both have locked multipliers, and neither is unlocked for overclocking.

FAQ

Q: Which processor has more cores?

A: The AMD Opteron 6238 has 12 cores and 12 threads. The Intel Core i7-3820QM has 4 cores and 8 threads.

Q: Do the two processors perform differently in Cinebench tests?

A: The recorded data shows the Opteron 6238 wins all six head-to-head Cinebench tests, but by very small margins. The largest lead is a 0.1% delta in R20 multicore, R23 multicore, and R23 single-core. The R15 multicore and single-core tests, plus the R20 single-core test, are exact ties.

Q: Which processor supports ECC memory?

A: The AMD Opteron 6238 supports ECC memory. The Intel Core i7-3820QM does not support ECC memory.

Q: What is the memory bus width for each processor?

A: The AMD Opteron 6238 uses a quad-channel memory bus with a bandwidth of 51.2 GB/s. The Intel Core i7-3820QM uses a dual-channel memory bus, and the database does not list a bandwidth figure for it.

Q: Does the Intel Core i7-3820QM have integrated graphics?

A: Yes, the Intel Core i7-3820QM includes integrated Intel HD 4000 graphics. The AMD Opteron 6238 has no integrated graphics.

Q: What are the power draws of these two processors?

A: The AMD Opteron 6238 has a TDP of 115 W. The Intel Core i7-3820QM has a TDP of 45 W.

Q: Which processor has a higher boost clock?

A: The Intel Core i7-3820QM boosts to 3.70 GHz, while the AMD Opteron 6238 boosts to 3.20 GHz. The Core i7 also has a higher base clock at 2.70 GHz versus 2.60 GHz.

Specification Differences

The two processors differ in nearly every major specification field. The Opteron 6238 has 12 cores and 12 threads, while the Core i7-3820QM has 4 cores and 8 threads. Base clocks are 2.60 GHz for the Opteron and 2.70 GHz for the Core i7. Boost clocks are 3.20 GHz and 3.70 GHz, respectively. TDP differs substantially: 115 W for the Opteron, 45 W for the Core i7.

Sockets are incompatible: the Opteron uses AMD Socket G34, while the Core i7 uses Intel BGA 1224. The Opteron is a server/workstation part, while the Core i7 is a mobile part. The Opteron's architecture is Bulldozer with the Interlagos codename, while the Core i7 uses Ivy Bridge. Process nodes differ: 32 nm for the Opteron at GlobalFoundries, 22 nm for the Core i7 at Intel. Transistor counts are 2,400 million for the Opteron and 1,400 million for the Core i7. Die sizes are 2x 315 mm² for the Opteron and 160 mm² for the Core i7.

Cache layouts differ. The Opteron has 768 KB of L1, 2 MB of L2 per module, and 8 MB of L3 per die. The Core i7 has 64 KB of L1 per core, 256 KB of L2 per core, and 8 MB of shared L3. Memory support: the Opteron uses quad-channel DDR3 with ECC support and 51.2 GB/s bandwidth; the Core i7 uses dual-channel DDR3 with no ECC support and no listed bandwidth. The Opteron has PCIe Gen 2, while the Core i7's PCIe support is not listed. The Core i7 has integrated Intel HD 4000 graphics; the Opteron has none.

Release dates differ: 2011-11-13 for the Opteron, 2012-04-28 for the Core i7. The Opteron has a launch MSRP of $455; the Core i7 has no launch MSRP. Both have locked multipliers. Part numbers are OS6238WKTCGGU for the Opteron and SR0MK for the Core i7. The Opteron is end-of-life, while the Core i7's production status is not listed.

Head-to-Head Benchmarks

The head-to-head data covers six Cinebench tests, and the Opteron 6238 wins all six. The results are remarkably consistent, with no test showing a meaningful performance gap.

In Cinebench R15 multicore, both processors score exactly 481. The delta is 0%, and the database credits the win to the Opteron 6238. This is a perfect tie in raw score.

In Cinebench R15 single-core, both processors again score exactly 67. The delta is 0%, and the Opteron is listed as the winner by tiebreak.

In Cinebench R20 multicore, the Opteron scores 2008 versus the Core i7's 2006. The delta is 0.1%, a two-point difference. This is the first test where the Opteron pulls ahead by a non-zero margin.

In Cinebench R20 single-core, both processors score exactly 283. The delta is 0%, and the Opteron wins by tiebreak again.

In Cinebench R23 multicore, the Opteron scores 4781 versus 4777 for the Core i7. The delta is 0.1%, a four-point difference.

In Cinebench R23 single-core, the Opteron scores 675 versus 674 for the Core i7. The delta is 0.1%, a one-point difference.

The database records 6 wins for the Opteron 6238 and 0 wins for the Core i7-3820QM. That sounds lopsided, but the magnitudes tell the real story. The largest delta in any test is 0.1%, which is within run-to-run noise for most benchmark suites. The aggregate average benchmark scores are 1383 for the Opteron and 1366 for the Core i7, a gap of roughly 1.2%. Both processors sit at the 36th percentile among all CPUs in the database.

For context, the Opteron 6238's nearest rivals are the Intel Core i7-3615QE (average score 1381, delta 0.2%), the Intel Core i3-9100TE (1386, delta -0.2%), the AMD Opteron 6366 HE (1379, delta 0.3%), and the AMD Opteron 6274 (1387, delta -0.3%). The Core i7-3820QM's nearest rivals are the Intel Xeon D-1521 (1367, delta -0.1%), the Intel Xeon E5-1410 v2 (1368, delta -0.2%), the AMD Opteron 6376 (1370, delta -0.3%), and the Intel Core i5-8365UE (1362, delta 0.3%). These rival deltas are all within a fraction of a percent, confirming that both chips sit in a very tight performance cluster.

The practical takeaway from the benchmark data is that the Opteron 6238 and Core i7-3820QM deliver essentially identical Cinebench performance. The 12-core, 12-thread Opteron does not translate its core advantage into a measurable multi-core lead, likely because the Core i7's higher clocks and efficient Ivy Bridge architecture compensate for its fewer cores. Conversely, the Core i7's higher boost clock does not give it a single-core lead either, as the single-core scores are tied or within one point. The two processors are performance peers in the database, with the Opteron holding a nominal edge that is unlikely to be perceptible in real-world applications.