AMD Opteron 6238 vs AMD Opteron 6376 Comparison

The AMD Opteron 6238 and AMD Opteron 6376 are both end-of-life server processors from AMD’s Opteron 6000 series, sharing the same socket, memory type, and 32 nm process node, but they represent different architectural generations and core configurations. Benchmark data from Cinebench R15, R20, and R23 shows the Opteron 6238 ahead in every single test, though the margins are consistently narrow, ranging from 0% to 1.1% depending on the workload. The Opteron 6376 counters with more physical cores and higher memory bandwidth, making the choice between them less about raw benchmark scores and more about workload characteristics and platform-level considerations.

FAQ

Q: Which processor has more physical cores?

A: The AMD Opteron 6376 has 16 cores and 16 threads, while the AMD Opteron 6238 has 12 cores and 12 threads. This gives the 6376 a 4-core advantage in multi-threaded workloads that can scale beyond 12 threads.

Q: How do their clock speeds compare?

A: The Opteron 6238 has a base clock of 2.60 GHz and a boost clock of 3.20 GHz. The Opteron 6376 has a lower base clock of 2.30 GHz but matches the 6238’s boost clock at 3.20 GHz. This means the 6238 starts at a higher frequency but both can reach the same maximum under boost.

Q: Are there any benchmark tests where the Opteron 6376 wins?

A: No. In the six head-to-head Cinebench tests (R15, R20, and R23, each with multi-core and single-core variants), the Opteron 6238 wins all six. The 6376’s best result is a tie in Cinebench R15 single-core, where both score 67.

Q: What is the average benchmark score difference between the two?

A: The Opteron 6238 has an average benchmark score of 1383, while the Opteron 6376 averages 1370. This puts the 6238 roughly 1% higher on average, which aligns with the individual test deltas of 0.8% to 1.1% favoring the 6238.

Q: Do they use the same memory architecture?

A: Both support DDR3 memory with a quad-channel memory bus and ECC support. However, the Opteron 6376 has a higher memory bandwidth at 59.7 GB/s compared to the Opteron 6238’s 51.2 GB/s, giving the 6376 a 16.6% bandwidth advantage.

Q: Which processor has a higher launch MSRP?

A: The AMD Opteron 6376 has a launch MSRP of $703, while the AMD Opteron 6238 has a launch MSRP of $455. The 6376 launched at a higher price point, consistent with its additional cores and newer architecture.

The Verdict

The data points to a clear but narrow victory for the AMD Opteron 6238 in pure benchmark performance. It wins all six Cinebench tests, with the largest margin being 1.1% in Cinebench R20 single-core (283 vs 280) and the smallest being a tie in R15 single-core (67 vs 67). In multi-core tests, the 6238 leads by 0.8% in R15 (481 vs 477) and 1% in both R20 (2008 vs 1989) and R23 (4781 vs 4736). This is a remarkable result given that the 6376 has 4 additional cores, suggesting the 6238’s higher base clock of 2.60 GHz versus 2.30 GHz compensates for the core deficit in these specific Cinebench workloads.

However, the verdict is not one-sided. The Opteron 6376’s 16 cores and higher memory bandwidth of 59.7 GB/s (versus 51.2 GB/s) make it the better choice for workloads that scale beyond 12 threads or are memory-bandwidth sensitive. The 6238’s advantage is consistent but small—never exceeding 1.1%—which means real-world differences will be negligible for most applications. For users with existing G34 platforms, the 6238 offers the better benchmark profile at a lower launch MSRP of $455 versus $703. But for new builds or workloads that can utilize all 16 cores of the 6376, the core count advantage may translate into better performance outside the Cinebench suite, even if the provided data does not show it.

Head-to-Head Benchmarks

The head-to-head results are remarkably consistent, with the Opteron 6238 winning every test by a margin between 0% and 1.1%. In Cinebench R15 multi-core, the 6238 scores 481 against the 6376’s 477, a 0.8% lead. The single-core R15 test is a dead heat at 67 points each. Moving to Cinebench R20, the 6238 extends its lead slightly: 2008 versus 1989 in multi-core (1% delta) and 283 versus 280 in single-core (1.1% delta). The pattern repeats in Cinebench R23, where the 6238 scores 4781 against 4736 in multi-core (1% delta) and 675 against 668 in single-core (1% delta).

These margins are tiny. A 1% difference in Cinebench R23 multi-core translates to just 45 points, which is within run-to-run variance for most systems. The 6238’s wins are consistent across all three Cinebench versions, which suggests a systematic advantage—likely its higher base clock—rather than a workload-specific quirk. But the 6376’s 16-core configuration means it should theoretically excel in heavily threaded workloads. The fact that it loses even in multi-core tests indicates that Cinebench’s scaling pattern does not favor the 6376’s extra cores, possibly due to the 6238’s higher frequency per module.

The average benchmark scores reinforce this picture: the 6238 averages 1383, while the 6376 averages 1370. In the context of their nearest rivals, the 6238 sits between the Intel Core i3-9100TE (1386, -0.2% delta) and the AMD Opteron 6366 HE (1379, 0.3% delta). The 6376 matches the Intel Core i7-2600 exactly at 1370 (0% delta) and edges out the Intel Xeon E5-1410 v2 (1368, 0.1% delta). Both processors land in the 36th percentile of all CPUs, indicating they are mid-pack performers by modern standards.

Specification Differences

The two processors differ in several key specifications. The Opteron 6238 has 12 cores and 12 threads, while the Opteron 6376 has 16 cores and 16 threads. Base clock speeds differ: 2.60 GHz for the 6238 versus 2.30 GHz for the 6376, though both share the same 3.20 GHz boost clock. Thermal design power is identical at 115 W for both, which is notable given the 6376’s additional cores—it achieves the same TDP with more cores but lower base frequency.

Memory bandwidth is another differentiator: the 6238 offers 51.2 GB/s, while the 6376 offers 59.7 GB/s, a 16.6% improvement. Both use DDR3 memory with quad-channel support and ECC, so the bandwidth difference likely comes from improved memory controllers in the 6376’s newer architecture. The launch MSRP also differs significantly: the 6238 launched at $455, the 6376 at $703.

Other specifications are identical: both use AMD Socket G34, have 768 KB of L1 cache, 2 MB of L2 cache per module, and 8 MB of L3 cache per die. Both have 2,400 million transistors, a 2x 315 mm² die size, PCIe Gen 2, and no integrated graphics. Neither has an unlocked multiplier. The part numbers differ (OS6238WKTCGGU vs OS6376WKTGGHK), and their release dates are about a year apart: November 2011 for the 6238 and November 2012 for the 6376.

Architecture Differences

The Opteron 6238 is built on the Bulldozer architecture, codenamed Interlagos, while the Opteron 6376 uses the newer Piledriver architecture, codenamed Abu Dhabi. Both are manufactured on a 32 nm process by GlobalFoundries, with identical transistor counts (2,400 million) and die sizes (2x 315 mm²). The architectural shift from Bulldozer to Piledriver brought several microarchitectural improvements, including better branch prediction, improved scheduling, and higher memory bandwidth (59.7 GB/s versus 51.2 GB/s).

Despite the architectural update, the cache hierarchy remains identical: 768 KB L1, 2 MB L2 per module, and 8 MB L3 per die. Both use a modular design where pairs of cores share L2 cache, a hallmark of the Bulldozer-derived architecture. The 6376’s Piledriver architecture also enables the same 3.20 GHz boost clock despite having more cores, though its base clock drops to 2.30 GHz. The 6238’s Bulldozer design achieves a higher base clock of 2.60 GHz. Both are end-of-life products with no integrated graphics and use PCIe Gen 2.

The core count difference (12 versus 16) is the most visible architectural distinction. The 6376 adds 4 more cores but keeps the same TDP of 115 W, which is why its base clock is lower. The Piledriver architecture in the 6376 is designed to be more efficient per core, allowing it to pack more cores into the same power envelope. However, benchmark data shows that this efficiency gain does not translate into higher Cinebench scores—the 6238’s higher base clock wins out in these tests.

Where Each One Wins

The AMD Opteron 6238 wins in every benchmark test provided, making it the default choice for workloads that resemble Cinebench’s rendering and 3D modeling tasks. It leads in multi-core tests by 0.8% to 1% and in single-core tests by 0% to 1.1%. Its higher base clock of 2.60 GHz gives it an edge in lightly threaded workloads and in tasks where frequency matters more than core count. For users running Cinebench specifically, or similar short-duration rendering tasks, the 6238 is the better performer despite having fewer cores.

The AMD Opteron 6376 wins in specifications that matter for different workloads. Its 16 cores versus 12 cores makes it the better choice for heavily threaded applications that can scale beyond 12 threads, such as video encoding, scientific simulations, or virtual machine hosting. Its memory bandwidth of 59.7 GB/s is 16.6% higher than the 6238’s, which benefits workloads that are memory-bandwidth bound, such as database operations or large data processing. The 6376 also launched with a higher MSRP of $703, reflecting its positioning as a higher-core-count part.

In practical terms, the benchmark data shows that the 6238 is the safer pick for general-purpose server work where you want the best Cinebench scores. The 6376 is the pick when you know your workload can use all 16 cores or when memory bandwidth is the bottleneck. Given that the 6376 loses by only 1% or less in multi-core tests despite having 33% more cores, the 6238’s per-core efficiency is impressive. But the 6376’s core count advantage is a real asset for scaling, even if it does not show up in these particular benchmarks.