AMD EPYC 9655 vs AMD EPYC 9965 Comparison

The AMD EPYC 9965 and AMD EPYC 9655 are both members of the EPYC 9005 series, sharing the Turin codename, SP5 socket, and a 576.0 GB/s twelve-channel DDR5 memory bus, yet they are engineered for distinctly different workloads. The 9965 is a 192-core, 384-thread Zen 5c part built on TSMC's 3 nm process, while the 9655 is a 96-core, 192-thread Zen 5 part on a 4 nm process. Benchmark data reveals a clear split: the 9965 dominates throughput-heavy tasks with massive parallel scaling, while the 9655 counters with superior single-thread performance and wins in specific latency-sensitive workloads.

Where Each One Wins

The AMD EPYC 9965 is the undisputed champion of raw multi-threaded throughput. Out of 17 head-to-head benchmark comparisons, it wins 13, with its most decisive victories coming in data compression (5,679,990 vs 3,271,896, a 73.6% delta), floating-point math (1,153,453 vs 662,958, a 74% delta), and integer math (1,926,069 vs 1,139,161, a 69.1% delta). Its 192 cores and 384 threads provide a massive parallel advantage that shows up most clearly in PassMark workloads that can scale across many cores. The 9965 also wins all six Cinebench tests, though by a narrow 3% margin in each case, indicating that its extra core count is not fully utilized in those specific rendering workloads.

The AMD EPYC 9655, by contrast, wins the four benchmarks where per-core efficiency and clock speed matter more than raw core count. Its most significant victory is in PassMark physics (25,947 vs 18,707, a 27.9% advantage), followed by find prime numbers (1,598 vs 1,208, a 24.4% advantage) and single-thread performance (3,847 vs 3,176, a 17.4% advantage). The 9655's higher base clock of 2.60 GHz and boost clock of 4.50 GHz, compared to the 9965's 2.25 GHz base and 3.70 GHz boost, are directly reflected in these single-threaded and latency-sensitive results. It also edges out the 9965 in PassMark multithread (156,110 vs 160,542), though the 9965 still wins that test by 2.8%, so the 9655's advantage is limited to workloads that cannot scale across all available cores.

The Verdict

The data indicates that the AMD EPYC 9965 is the superior choice for environments where workloads can fully utilize 192 cores and 384 threads. Its average benchmark score of 620,487 places it 18.5% ahead of the AMD EPYC 9845, its closest rival, and 50.6% ahead of the AMD Ryzen Threadripper PRO 9995WX. For data compression, encryption, extended instruction sets, and heavy math workloads, the 9965 offers performance gains ranging from 44% to 88.6% over the 9655. These are not marginal differences; they represent near-doubling of performance in specific parallel tasks. The 9965 also maintains a 100th percentile ranking among all CPUs, matching the 9655's percentile but with a significantly higher absolute score.

The AMD EPYC 9655 is the better pick for workloads that are single-threaded or latency-bound, or where the 96-core count is sufficient. Its 17.4% lead in PassMark single-thread performance and 27.9% lead in physics simulations make it the more responsive processor for those specific tasks. Its average benchmark score of 373,479 is only 1.6% behind the AMD EPYC 9535, its closest rival, and it beats the Intel Xeon 6960P by 2.3%. For users who need strong multi-threaded performance but do not require 192 cores, the 9655 offers a more balanced profile, though its multicore scores are consistently 3% lower than the 9965 across Cinebench tests.

Head-to-Head Benchmarks

The most striking divergence between these two processors appears in the PassMark suite. In data compression, the 9965 scores 5,679,990 against the 9655's 3,271,896, a 73.6% advantage that represents the largest single delta in the entire comparison. Similarly, floating-point math shows a 74% gap (1,153,453 vs 662,958), and integer math shows a 69.1% gap (1,926,069 vs 1,139,161). Extended instructions see the 9965 at 383,298 versus 203,285, an 88.6% lead that is the highest percentage difference recorded. Data encryption follows at 65.5% (348,449 vs 210,555), and random string sorting at 44% (633,030 vs 439,682). These results clearly demonstrate that the 9965's 192 cores scale almost linearly in workloads designed for massive parallelism.

The 9655's wins, while fewer, are equally telling. In PassMark physics, it scores 25,947 versus the 9965's 18,707, a 27.9% advantage that suggests superior handling of physics calculations that may rely on higher clock speeds. Find prime numbers shows a 24.4% edge (1,598 vs 1,208), and single-thread performance is 17.4% higher (3,847 vs 3,176). The Cinebench results are remarkably consistent: the 9965 wins all six tests by exactly 3%, from R15 multicore (13,775 vs 13,373) to R23 multicore (136,661 vs 132,672). This consistency suggests that Cinebench's rendering workload does not fully exploit the 9965's additional cores, but the 9965 still maintains a lead due to its superior thread count. The PassMark multithread test is the closest overall result, with the 9965 winning by a slim 2.8% (160,542 vs 156,110).

FAQ

Q: Which processor has more cores and threads?

A: The AMD EPYC 9965 has 192 cores and 384 threads, while the AMD EPYC 9655 has 96 cores and 192 threads.

Q: What is the single-thread performance difference?

A: The AMD EPYC 9655 wins PassMark single-thread with a score of 3,847, which is 17.4% higher than the 9965's 3,176.

Q: How do the Cinebench R23 multicore scores compare?

A: The AMD EPYC 9965 scores 136,661 in Cinebench R23 multicore, while the 9655 scores 132,672, giving the 9965 a 3% advantage.

Q: Which processor has a higher boost clock?

A: The AMD EPYC 9655 has a boost clock of 4.50 GHz, compared to the 9965's 3.70 GHz.

Q: What is the biggest performance gap between them?

A: The largest delta is in PassMark extended instructions, where the 9965 scores 383,298 versus the 9655's 203,285, an 88.6% lead.

Q: Are both processors in the same generation?

A: Yes, both are from the EPYC 9005 series with the Turin codename, but the 9965 uses Zen 5c architecture on a 3 nm process, while the 9655 uses Zen 5 on a 4 nm process.

Architecture Differences

The architectural split between these two processors is fundamental. The AMD EPYC 9965 uses Zen 5c (Turin) architecture on a 3 nm TSMC process, while the 9655 uses standard Zen 5 (Turin) on a 4 nm TSMC process. The 9965 doubles the core count to 192 and threads to 384, but this comes at the cost of lower clock speeds: a 2.25 GHz base and 3.70 GHz boost, versus the 9655's 2.60 GHz base and 4.50 GHz boost. Both processors share identical cache configurations: 80 KB of L1 per core, 1 MB of L2 per core, and 384 MB of shared L3 cache. The 9965's TDP is 500, while the 9655's is 400, reflecting the higher power draw of the additional cores.

The 9655's transistor count is listed at 99,780 million across 12 dies of 70.6 mm² each, while the 9965's transistor count and die size are not specified. This suggests that the 9965's denser 3 nm process allows for more cores within a similar power envelope, though its higher TDP of 500 indicates the scaling is not free. Both processors support DDR5 memory over a twelve-channel bus with 576.0 GB/s bandwidth, and both offer PCIe Gen 5 with 128 lanes (CPU only). Neither has integrated graphics, and both use the AMD Socket SP5. The release date for both is October 9, 2024, with the 9965's launch MSRP at $14,813 and the 9655's at $11,852. The 9965's part number is 100-000000976, while the 9655's is 100-000000674, and both are currently in active production.