AMD EPYC 4545P vs AMD Ryzen 9 8945HX Comparison

The AMD Ryzen 9 8945HX and AMD EPYC 4545P are both 16-core, 32-thread Zen-family processors, yet they target completely different worlds: one is a mobile flagship for high-end laptops, the other a server/workstation part on a desktop socket. Benchmark data shows the EPYC 4545P wins 13 of 17 head-to-head tests, while the Ryzen 8945HX takes 4. However, the nature of those wins reveals that neither chip is a universal champion—the choice depends entirely on the workload.

Where Each One Wins

The AMD Ryzen 9 8945HX is the clear winner in data compression and encryption workloads. It scores 677,755 in Passmark data compression, a 6.5% edge over the EPYC 4545P's 636,279. In data encryption, the mobile chip posts 40,836 versus 37,598, an 8.6% advantage. It also leads in extended instructions (49,823 vs 46,231, +7.8%) and random string sorting (78,781 vs 73,850, +6.7%). These are classic memory-latency-sensitive and cryptography-heavy tasks, where the Ryzen 9's design clearly has an edge.

The AMD EPYC 4545P dominates nearly everywhere else. Its biggest margin comes in Passmark physics, scoring 3,260 against the Ryzen 9's 2,168—a massive 33.5% lead. It also wins all six Cinebench tests (R15, R20, R23, both single- and multi-core) by a consistent 9.3% margin. In pure integer math, floating-point math, and prime number finding, the EPYC is ahead by 8.6%, 7.2%, and 10.3% respectively. The overall Passmark multithread score also favors the EPYC: 53,504 vs 51,405 (+3.9%). If the workload is render-heavy, physics-simulated, or generally compute-dense, the EPYC 4545P is the stronger part.

Architecture Differences

The two chips come from different process generations and microarchitectures. The Ryzen 9 8945HX is built on Zen 4 (Dragon Range) using a 5 nm process from TSMC, while the EPYC 4545P uses Zen 5 (Grado) on a 4 nm TSMC node. The transistor counts reflect this: the Ryzen packs 13,140 million transistors across a 2x 71 mm² die, while the EPYC has 16,630 million transistors on a 2x 70.6 mm² die. The newer process and architecture give the EPYC a denser, more efficient design.

Cache layouts differ at the L1 level. The Ryzen 9 has 64 KB of L1 per core, while the EPYC has 80 KB per core. Both share 1 MB of L2 per core and 64 MB of L3 total. The EPYC's larger L1 could contribute to its lead in integer and floating-point math, where per-thread data reuse matters.

Memory and platform support also diverge. Both support DDR5 dual-channel, but the EPYC 4545P has higher memory bandwidth at 89.6 GB/s versus the Ryzen 9's 83.2 GB/s. The EPYC supports ECC memory; the Ryzen 9 does not. The Ryzen 9 offers 28 PCIe Gen 5 lanes (CPU only), while the EPYC provides 24 PCIe Gen 5 lanes. The Ryzen 9 uses AMD Socket FL1 and has an unlocked multiplier, whereas the EPYC uses AMD Socket AM5 and is locked. Integrated graphics differ too: the Ryzen 9 has Radeon 610M, while the EPYC includes Radeon Graphics. The EPYC's launch MSRP is $549.

The power envelopes are telling. The Ryzen 9 8945HX is rated at 55 W TDP, designed for mobile systems where heat and battery matter. The EPYC 4545P is a 65 W part, aimed at always-plugged-in server/workstation environments. The EPYC's higher base clock of 3.00 GHz (versus 2.50 GHz) and identical 5.40 GHz boost clock suggest it can sustain higher sustained performance under load, which the benchmark scores confirm.

Head-to-Head Benchmarks

The Cinebench suite shows a uniform 9.3% win for the EPYC 4545P across all tests. In R15 multicore, the EPYC scores 4,745 against the Ryzen 9's 4,305. R15 single-core: 669 vs 607. R20 multicore: 19,773 vs 17,939. R20 single-core: 2,791 vs 2,532. R23 multicore: 47,079 vs 42,713. R23 single-core: 6,646 vs 6,030. This consistency indicates the EPYC's Zen 5 architecture provides a uniform IPC advantage over Zen 4 in render workloads, regardless of thread count.

The Passmark physics test is the single largest gap. The EPYC's 3,260 score is 33.5% higher than the Ryzen 9's 2,168. This is a dramatic difference that suggests the EPYC's architecture handles the physics simulation workload far more efficiently, likely benefiting from the larger L1 cache and newer core design.

The Ryzen 9 8945HX's wins are also notable. In data compression, it beats the EPYC by 6.5% (677,755 vs 636,279). Data encryption shows an 8.6% lead (40,836 vs 37,598). Extended instructions are 7.8% better (49,823 vs 46,231), and random string sorting is 6.7% ahead (78,781 vs 73,850). These are not small margins—they indicate the Ryzen 9's memory subsystem or instruction scheduling handles these specific patterns better, despite the EPYC's higher memory bandwidth.

Single-thread performance favors the EPYC by 9.5% in Passmark (4,318 vs 3,907), but the Cinebench single-core tests show only a 9.3% gap. Integer math goes to the EPYC by 8.6% (213,485 vs 195,180), and floating-point math by 7.2% (126,505 vs 117,453). Prime number finding is a 10.3% EPYC win (292 vs 262). The overall Passmark multithread score is closer, with the EPYC ahead just 3.9% (53,504 vs 51,405). Both chips sit at the 95th percentile of all CPUs, and their average benchmark scores are within 1.1% of each other (76,212 vs 75,373), placing them in the same performance tier.

The Verdict

The data is clear: for raw compute performance in rendering, physics, and math-heavy workloads, the AMD EPYC 4545P is the superior chip. It wins 13 of 17 benchmarks, including every Cinebench test and the most demanding Passmark workloads. Its 33.5% physics lead and consistent 9.3% Cinebench advantage make it the obvious choice for server or workstation tasks where sustained multi-threaded performance is critical.

The AMD Ryzen 9 8945HX, despite its mobile 55 W TDP, wins the encryption, compression, and string-sorting tests. For users who prioritize data compression, encryption, or extended instruction workloads, the Ryzen 9 offers a 6.5% to 8.6% edge. However, its 4 wins versus 13 losses mean it is not the general-purpose performance king.

Choose the EPYC 4545P if you need ECC memory support, higher memory bandwidth (89.6 GB/s), and the strongest multi-core rendering and math performance. It is built for always-on reliability and throughput. Choose the Ryzen 9 8945HX if your workflows are dominated by data compression, encryption, or random string sorting, and if you require the flexibility of an unlocked multiplier and a mobile socket. The Ryzen 9 also offers 28 PCIe Gen 5 lanes versus the EPYC's 24, which matters for storage or GPU expansion. Both are 95th-percentile performers, but the EPYC's architecture wins the majority of head-to-head battles.

FAQ

Q: Which CPU has better single-core performance?

A: The AMD EPYC 4545P wins in single-core tests. It scores 6,646 in Cinebench R23 single-core versus the Ryzen 9 8945HX's 6,030, a 9.3% lead. Passmark single-thread also favors the EPYC: 4,318 vs 3,907 (+9.5%).

Q: How do they compare in multi-core rendering?

A: The EPYC 4545P leads in all Cinebench multi-core tests by 9.3%. In Cinebench R23 multi-core, it scores 47,079 versus the Ryzen 9's 42,713. The Passmark multithread score is closer, with the EPYC ahead 53,504 vs 51,405 (+3.9%).

Q: Does the Ryzen 9 8945HX win any benchmark?

A: Yes, it wins 4 tests: Passmark data compression (677,755 vs 636,279, +6.5%), data encryption (40,836 vs 37,598, +8.6%), extended instructions (49,823 vs 46,231, +7.8%), and random string sorting (78,781 vs 73,850, +6.7%).

Q: What is the biggest performance gap between the two?

A: The largest gap is in Passmark physics, where the EPYC 4545P scores 3,260 versus the Ryzen 9's 2,168—a 33.5% difference. The smallest gap is in Passmark multithread, at 3.9%.

Q: Do they support the same memory features?

A: Both support DDR5 dual-channel memory. The EPYC 4545P has higher bandwidth (89.6 GB/s vs 83.2 GB/s) and supports ECC memory. The Ryzen 9 8945HX does not support ECC.

Q: Which chip has more PCIe lanes?

A: The Ryzen 9 8945HX provides 28 PCIe Gen 5 lanes (CPU only), while the EPYC 4545P provides 24 PCIe Gen 5 lanes.