AMD EPYC 9654P vs AMD Ryzen 9 5900HX Comparison

FAQ

Q: Which processor has more cores and threads?

A: The AMD EPYC 9654P has 96 cores and 192 threads, while the AMD Ryzen 9 5900HX has 8 cores and 16 threads.

Q: What is the difference in process node between the two chips?

A: The AMD Ryzen 9 5900HX is built on a 7 nm process, while the AMD EPYC 9654P uses a 5 nm process. Both are manufactured by TSMC.

Q: How do the two processors compare in single-threaded Geekbench performance?

A: The AMD EPYC 9654P scores 1981 in Geekbench single-core, which is 9.5% higher than the AMD Ryzen 9 5900HX's 1792.

Q: Which processor supports ECC memory?

A: The AMD EPYC 9654P supports ECC memory, while the AMD Ryzen 9 5900HX does not.

Q: What memory types do the two chips support?

A: The AMD Ryzen 9 5900HX supports DDR4 memory with a dual-channel bus, while the AMD EPYC 9654P supports DDR5 memory with a twelve-channel bus.

Q: What is the market segment for each processor?

A: The AMD Ryzen 9 5900HX is designed for the mobile segment, while the AMD EPYC 9654P is a server/workstation processor.

Where Each One Wins

The benchmark results show a clear split in workloads where each processor excels. The AMD EPYC 9654P wins every head-to-head benchmark in the database, taking all six recorded tests. However, the size of those wins varies dramatically by workload type.

The EPYC 9654P dominates in heavily multi-threaded workloads. In Cinebench R23 multi-core, it scores 98875 versus 12845 for the Ryzen 9 5900HX, a gap of 87%. The Cinebench R15 multi-core test shows a similar pattern, with the EPYC scoring 9966 against 2106, a 78.9% advantage. This is the expected outcome given 96 cores versus 8 cores.

The Ryzen 9 5900HX is not without its advantages in context. Its 45 W TDP makes it suitable for mobile systems, whereas the EPYC 9654P has a 360 W TDP and is a server part. The Ryzen chip also includes integrated Radeon Vega 8 graphics, which the EPYC lacks entirely.

The closest contest is in Geekbench single-core, where the EPYC 9654P leads by only 9.5% (1981 versus 1792). This indicates that for lightly threaded tasks, the architectural gap between the two is much narrower than the core count difference suggests.

Architecture Differences

These two processors come from different generations and design philosophies. The AMD Ryzen 9 5900HX is based on Zen 3 architecture, codenamed Cezanne, and belongs to the 5000 series. The AMD EPYC 9654P uses Zen 4 architecture, codenamed Genoa, and belongs to the EPYC 9004 series.

The process node differs significantly. The Ryzen 9 5900HX uses a 7 nm process, while the EPYC 9654P uses a 5 nm process, both from TSMC. Transistor counts reflect the scale difference: the Ryzen chip has 10,700 million transistors on a 180 mm² die, while the EPYC has 78,840 million transistors spread across 12 dies of 72 mm² each.

Cache hierarchies differ substantially. Both have 64 KB of L1 cache per core. The L2 cache is 512 KB per core on the Ryzen versus 1 MB per core on the EPYC. The L3 cache is the largest differentiator: 16 MB shared on the Ryzen against 384 MB shared on the EPYC.

Memory architecture is a major divergence. The Ryzen 9 5900HX uses DDR4 with a dual-channel bus and 68.3 GB/s bandwidth. The EPYC 9654P uses DDR5 with a twelve-channel bus and 460.8 GB/s bandwidth. ECC memory support exists only on the EPYC.

PCIe capabilities also differ. The Ryzen chip supports PCIe Gen 3, while the EPYC supports PCIe Gen 5 with 128 lanes (CPU only). The integrated graphics situation is another contrast: the Ryzen 9 5900HX has Radeon Vega 8, while the EPYC 9654P has no integrated graphics at all.

Specification Differences

The core counts are the most obvious difference: 8 cores and 16 threads on the Ryzen 9 5900HX versus 96 cores and 192 threads on the EPYC 9654P.

Clock speeds tell a nuanced story. The Ryzen has a higher base clock of 3.30 GHz and a higher boost clock of 4.60 GHz. The EPYC runs at 2.40 GHz base and 3.70 GHz boost. Despite lower clocks, the EPYC wins every benchmark due to its massive core advantage.

TDP is a stark contrast: 45 W for the Ryzen versus 360 W for the EPYC. Sockets are entirely different as well, with the Ryzen using AMD Socket FP6 and the EPYC using AMD Socket SP5.

Memory specifications differ completely. The Ryzen supports DDR4 with dual-channel memory and 68.3 GB/s bandwidth. The EPYC supports DDR5 with twelve-channel memory and 460.8 GB/s bandwidth. ECC memory is supported only on the EPYC.

Cache configurations diverge at the L2 and L3 levels. Both share 64 KB L1 per core, but the Ryzen has 512 KB L2 per core versus 1 MB L2 per core on the EPYC. L3 cache is 16 MB shared on the Ryzen versus 384 MB shared on the EPYC.

PCIe generation differs: Gen 3 on the Ryzen versus Gen 5 with 128 lanes on the EPYC. The Ryzen includes Radeon Vega 8 integrated graphics; the EPYC has none. The Ryzen has an unlocked multiplier, while the EPYC does not.

Release dates differ by nearly two years. The Ryzen 9 5900HX launched on 2021-01-11, and the EPYC 9654P launched on 2022-11-09. The EPYC has a launch MSRP of $10625.

Head-to-Head Benchmarks

The database records six head-to-head comparisons, and the AMD EPYC 9654P wins all six. The margin varies considerably across tests.

The largest single advantage appears in Cinebench R23 single-core, where the EPYC scores 13958 against 1488 for the Ryzen, a 89.3% difference. This is the largest percentage gap in any recorded test. Cinebench R23 multi-core shows a similar 87% gap, with scores of 98875 for the EPYC versus 12845.

Cinebench R15 results follow the same pattern. Multi-core scores are 9966 for the EPYC versus 2106 for the Ryzen, a 78.9% difference. Single-core in R15 shows 1406 against 240, an 82.9% gap.

Geekbench results show a more moderate spread. The multi-core test gives the EPYC 22141 versus 8720 for the Ryzen, a 60.6% advantage. The single-core test is the closest contest in the entire comparison: 1981 for the EPYC versus 1792 for the Ryzen, only a 9.5% difference.

Wins are recorded as six for the EPYC and zero for the Ryzen 9 5900HX. The average benchmark score in the database is 24822 for the Ryzen and 24465 for the EPYC, placing both at the 77th percentile among all CPUs.

The Ryzen 9 5900HX has additional benchmark data that the EPYC lacks, including 3DMark results and Passmark tests. These include a 3DMark single-thread score of 881, a 3DMark max-threads score of 6487, and Passmark multithread score of 22326. However, no direct head-to-head comparison exists for these tests against the EPYC.

The Verdict

The data supports a straightforward conclusion: the AMD EPYC 9654P is the overwhelmingly faster processor in every recorded head-to-head benchmark. Its 96 cores and 192 threads deliver 87% higher Cinebench R23 multi-core performance and 60.6% higher Geekbench multi-core performance than the Ryzen 9 5900HX. For server workloads, database operations, and heavily parallel compute tasks, the EPYC 9654P is the clear choice.

The AMD Ryzen 9 5900HX serves a completely different purpose. Its 45 W TDP, integrated Radeon Vega 8 graphics, and mobile socket (FP6) place it in laptops and compact systems. The higher boost clock of 4.60 GHz helps in light-threaded tasks, though even there the EPYC leads by 9.5% in Geekbench single-core.

The closest comparison point is single-threaded performance, where the EPYC's Zen 4 architecture at 5 nm overcomes its lower clock speeds to edge ahead by 9.5%. This suggests that for single-threaded responsiveness, neither chip has a dramatic advantage over the other, but the EPYC still leads.

Users who need a mobile processor with integrated graphics should pick the Ryzen 9 5900HX. Users who need maximum multi-threaded throughput, ECC memory support, DDR5 with twelve-channel bandwidth, and PCIe Gen 5 connectivity should pick the EPYC 9654P. The 360 W TDP and server socket make the EPYC unsuitable for consumer desktop or mobile use, just as the Ryzen's 8 cores cannot match server-scale performance demands.