AMD EPYC 7643P vs AMD EPYC 9275F Comparison

The AMD EPYC 7643P and AMD EPYC 9275F are both high-end server processors aimed at dense compute workloads, but they approach the job from opposite directions. The 7643P is a 48-core Zen 3 part built on the older SP3 platform, while the 9275F is a 24-core Zen 5 part on the newer SP5 platform. Benchmark results show a clear split: the 9275F dominates in single-threaded and lightly threaded tasks, while the 7643P takes several multi-threaded and data-heavy workloads. This analysis breaks down where each chip wins, what the numbers mean for real-world use, and which buyer should choose which.

Head-to-Head Benchmarks

The most striking pattern in the head-to-head data is the 9275F’s near-sweep of the Cinebench suite. Across all six Cinebench tests—R15, R20, and R23, each in both single-core and multi-core variants—the 9275F wins by a consistent margin of roughly 8.6% to 8.7%. For example, in Cinebench R23 multi-core, the 9275F scores 71927 against the 7643P’s 65710, a delta of -8.6% from the 7643P’s perspective. The single-core results are similarly lopsided: Cinebench R23 single-core shows 10154 for the 9275F versus 9276 for the 7643P, an 8.6% gap. This consistency suggests a fundamental architectural advantage for the 9275F in rendering-style workloads, not just a one-off benchmark quirk.

PassMark results tell a more nuanced story. The 9275F wins in passmark_multithread (84620 vs 77307, -8.6%), passmark_single_thread (3810 vs 2655, -30.3%), passmark_extended_instructions (94889 vs 67398, -29%), passmark_find_prime_numbers (991 vs 651, -34.3%), and passmark_physics (12089 vs 8002, -33.8%). The single-thread and physics wins are particularly large—the 9275F is about 30% ahead in single-thread score and nearly 34% ahead in physics. The extended instructions and prime number results show similar magnitude advantages, indicating that the 9275F’s newer Zen 5 cores are substantially more efficient per thread at complex instruction streams and integer-heavy calculations.

However, the 7643P fights back in several PassMark subtests where its higher core count (48 vs 24) and larger thread pool (96 vs 48) overwhelm the per-core advantage of the 9275F. The 7643P wins passmark_data_compression (1326051 vs 1212560, a 9.4% delta), passmark_data_encryption (95606 vs 62664, a massive 52.6% delta), passmark_floating_point_math (216592 vs 201888, 7.3%), passmark_integer_math (390775 vs 317777, 23%), and passmark_random_string_sorting (160274 vs 144037, 11.3%). The encryption result is the single biggest win for either side—the 7643P outperforms the 9275F by over half in this workload, which points to the 7643P’s multi-threaded scaling capability being far superior when the task parallelizes well.

Looking at overall average benchmark scores, the 7643P comes out ahead: its avgBenchmarkScore is 144824, while the 9275F sits at 133174. That’s an 8.7% advantage for the 7643P in the aggregate. The nearestRivals data corroborates this: the 7643P’s rivals list includes the 9275F with a deltaPct of 8.7%, meaning the 9275F is that far behind the 7643P on average. Conversely, the 9275F’s rivals list shows the 7643P with a deltaPct of -8%, meaning the 7643P is 8% ahead. The 9275F does beat other rivals like the AMD EPYC 9354 (by 5%) and the AMD Ryzen Threadripper PRO 5975WX (by 7.3%), but it cannot match the 7643P’s overall throughput.

The Verdict

If you prioritize raw multi-threaded throughput across a wide range of server workloads, the data clearly favors the AMD EPYC 7643P. Its average benchmark score is 8.7% higher than the 9275F, and it wins in five of the seventeen head-to-head tests, including the high-impact areas of data encryption, integer math, and data compression. The 7643P’s 48 cores and 96 threads provide a massive parallelism advantage that shows up in workloads that scale linearly with core count. For database servers, compression pipelines, or encryption-heavy tasks, the 7643P is the stronger choice.

On the other hand, the AMD EPYC 9275F is the pick for workloads that are latency-sensitive or single-thread-bound. It wins twelve of the seventeen benchmarks, and its single-thread score of 3810 is 30.3% higher than the 7643P’s 2655. The physics test shows a 33.8% advantage, and extended instructions are 29% better. If your application is dominated by a few fast cores, or if you need the highest possible per-core performance for things like simulation solvers or real-time analytics, the 9275F’s Zen 5 architecture delivers meaningfully better responsiveness.

The choice is not about which CPU is “better” overall—it’s about workload profile. The 7643P is a throughput monster that wins on aggregate scores; the 9275F is a per-core powerhouse that wins in latency-bound scenarios. Both sit in the 98th percentile of all CPUs, so neither is a weak option. But the 8.7% average score gap means the 7643P is the safer default for mixed server workloads, while the 9275F is the specialist tool for speed-critical single-threaded tasks.

FAQ

Q: Which CPU has the higher average benchmark score?

A: The AMD EPYC 7643P has an avgBenchmarkScore of 144824, while the AMD EPYC 9275F scores 133174. That’s an 8.7% delta in favor of the 7643P.

Q: How much faster is the 9275F in single-threaded performance?

A: In PassMark single-thread testing, the 9275F scores 3810 versus the 7643P’s 2655, a 30.3% advantage. The Cinebench R23 single-core test shows a smaller but still consistent gap: 10154 vs 9276, an 8.6% difference.

Q: What is the biggest benchmark win for the 7643P?

A: The 7643P’s largest victory is in PassMark data encryption, where it scores 95606 against the 9275F’s 62664—a 52.6% delta. It also wins integer math by 23% and random string sorting by 11.3%.

Q: Does the 9275F win any multi-core benchmarks?

A: Yes, the 9275F wins all Cinebench multi-core tests. In Cinebench R23 multi-core, it scores 71927 versus 65710 for the 7643P, an 8.6% advantage. It also wins PassMark multithread with 84620 versus 77307.

Q: Which CPU has more cores and threads?

A: The AMD EPYC 7643P has 48 cores and 96 threads. The AMD EPYC 9275F has 24 cores and 48 threads—exactly half.

Q: How does the 9275F compare to other rivals besides the 7643P?

A: The 9275F’s nearest rivals include the AMD EPYC 9354 (5% ahead), the AMD Ryzen Threadripper PRO 5975WX (7.3% ahead), and the AMD EPYC 7642 (7.4% ahead). It only trails the 7643P among its listed rivals.

Specification Differences

The two processors differ on nearly every core specification. The AMD EPYC 7643P offers 48 cores and 96 threads, while the AMD EPYC 9275F halves that to 24 cores and 48 threads. Base clock speeds are starkly different: the 7643P runs at 2.30 GHz base and 3.60 GHz boost, whereas the 9275F runs at 4.10 GHz base and 4.80 GHz boost. Thermal design power also diverges—the 7643P is rated at 225 watts, the 9275F at 320 watts.

The socket and platform generations are incompatible. The 7643P uses AMD Socket SP3, while the 9275F uses AMD Socket SP5. Memory support differs as well: the 7643P supports DDR4 with an eight-channel memory bus and 204.8 GB/s bandwidth, while the 9275F supports DDR5 with a twelve-channel bus and 576.0 GB/s bandwidth. Both support ECC memory. PCIe capabilities are similar in lane count—both offer 128 lanes from the CPU—but the 7643P is Gen 4 while the 9275F is Gen 5.

Cache layouts also differ. The 7643P has 64 KB of L1 per core and 512 KB of L2 per core, with 256 MB of shared L3. The 9275F has 80 KB of L1 per core and 1 MB of L2 per core, also with 256 MB of shared L3. Neither chip has 3D V-Cache. The 7643P has a launch MSRP of $2722; the 9275F has a launch MSRP of $3439. Both are active production parts, neither has an unlocked multiplier, and both target the server/workstation market segment.

Architecture Differences

The architectural gap between these two is generational. The AMD EPYC 7643P is built on Zen 3, codenamed Milan, using a 7 nm process from TSMC. It packs 33,200 million transistors across 8 dies, each 81 mm². The AMD EPYC 9275F is built on Zen 5, codenamed Turin, using a 4 nm process from the same foundry. Its transistor count jumps to 66,520 million, spread across 8 dies that are each 70.6 mm². The smaller process node and higher transistor density give the 9275F a significant efficiency advantage per core, which explains its much higher clock speeds despite a 95-watt higher TDP.

The cache hierarchy reflects the architectural shift. The 7643P’s L1 is 64 KB per core and L2 is 512 KB per core; the 9275F increases L1 to 80 KB per core and L2 to 1 MB per core. Both share 256 MB of L3, but the larger per-core L2 on the 9275F helps with single-threaded data locality. The memory controller also moves from DDR4 eight-channel to DDR5 twelve-channel, nearly tripling memory bandwidth from 204.8 GB/s to 576.0 GB/s. The PCIe interface advances from Gen 4 to Gen 5, doubling the potential I/O bandwidth per lane, though both maintain 128 lanes.

The release timeline and platform support also differ. The 7643P launched as part of the Milan generation, while the 9275F is a Turin part, placing it a full architectural generation ahead. The process node shrinkage from 7 nm to 4 nm is the primary enabler of the 9275F’s higher clocks and per-core performance, while the 7643P relies on doubling the core count to compete in throughput.

Where Each One Wins

The AMD EPYC 7643P is the winner in workloads that scale with core count and thread parallelism. PassMark data encryption is its standout victory, with a 52.6% delta over the 9275F, followed by integer math at 23% and random string sorting at 11.3%. Data compression also goes to the 7643P by 9.4%, and floating-point math by 7.3%. These results point to use cases like database query processing, batch encryption/decryption, data warehousing compression, and any parallel integer-heavy compute. The 7643P’s higher core count—double that of the 9275F—allows it to sustain higher aggregate throughput in these scenarios, even if each individual core is slower.

The AMD EPYC 9275F is the clear winner in single-threaded and latency-sensitive workloads. Its PassMark single-thread score is 30.3% higher, and it wins the physics test by 33.8%, extended instructions by 29%, and prime number finding by 34.3%. Every Cinebench test—single and multi-core—goes to the 9275F by roughly 8.6%, which suggests that even in rendering tasks that typically favor more cores, the 9275F’s per-core speed compensates for having half the cores. This makes the 9275F the better choice for real-time analytics, simulation solvers, high-frequency trading, or any application where the critical path runs through a handful of threads.

The aggregate benchmark score, however, tilts toward the 7643P. Its avgBenchmarkScore of 144824 is 8.7% higher than the 9275F’s 133174, and both CPUs rank in the