AMD EPYC 9135 vs AMD Ryzen 9 8945HX Comparison

Head-to-Head Benchmarks

The benchmark data is heavily one-sided. The AMD EPYC 9135 wins 14 of the 17 recorded comparisons, and the margins are often substantial. The most dramatic result is in PassMark Physics, where the EPYC 9135 scores 5,477 against the Ryzen 9 8945HX's 2,168. That is a 152.6% advantage, a gap so large that it points to a fundamentally different performance envelope rather than a minor architectural edge.

Cinebench results follow a consistent pattern. The EPYC 9135 leads by 15% in Cinebench R15 multi-core (4,952 vs 4,305), R20 multi-core (20,637 vs 17,939), R23 multi-core (49,136 vs 42,713), and R23 single-core (6,936 vs 6,030). The single-core R15 and R20 deltas are 15.2% and 15% respectively, so the EPYC's advantage is not just about core scaling; it also wins on lightly threaded workloads.

PassMark integer math shows a narrower win for the EPYC 9135 at 202,962 vs 195,180, a 4% delta. Floating point math goes to the EPYC by 7.9% (126,679 vs 117,453). Data compression is a 9.1% win for the EPYC at 739,277 vs 677,755. Extended instructions favor the EPYC by 12%, and prime number finding by 11.5%.

The Ryzen 9 8945HX does have two clear wins, both in single-threaded PassMark tests. It scores 3,907 in PassMark single-thread versus the EPYC's 3,672, a 6% advantage. That result appears twice in the data, once as "passmark_single_thread" and once as "passmark_singlethread." The Ryzen also edges out the EPYC in data encryption, scoring 40,836 vs 40,295, a 1.3% lead.

The overall average benchmark score tells the same story. The EPYC 9135 averages 82,980, while the Ryzen 9 8945HX averages 76,212. The EPYC also sits at the 96th percentile among all CPUs, one point above the Ryzen's 95th percentile. Looking at nearest rivals, the EPYC is essentially tied with the AMD EPYC 4584PX (delta of -0.1%) and about 1% behind the Intel Core Ultra 9 285K. The Ryzen 9 8945HX, by contrast, is nearly tied with the Intel Core Ultra 9 285HX (delta of 0.1%) and the AMD Ryzen 9 9950X3D (delta of 0.6%). In short, the EPYC 9135 is the stronger performer in nearly every measurable category.

Architecture Differences

The two chips come from different generations of AMD design. The EPYC 9135 is built on Zen 5 architecture with the codename Turin, while the Ryzen 9 8945HX uses Zen 4 with the codename Dragon Range. The manufacturing process differs as well: the EPYC is fabbed on a 4 nm node at TSMC, whereas the Ryzen uses a 5 nm node at the same foundry.

Both processors have 16 cores and 32 threads, so the thread count is identical. The cache hierarchy is broadly similar in capacity, with each core getting 1 MB of L2 and 64 MB of shared L3 on both chips. The L1 cache differs: the EPYC has 80 KB per core, the Ryzen has 64 KB per core. The EPYC's transistor count is 16,630 million across a die size of 2x 70.6 mm². The Ryzen has 13,140 million transistors on a die size of 2x 71 mm². The die areas are close, but the EPYC packs significantly more transistors onto a slightly smaller total footprint.

Clock speeds are a major differentiator. The EPYC 9135 has a base clock of 3.65 GHz and a boost of 4.30 GHz. The Ryzen 9 8945HX has a much lower base clock of 2.50 GHz but a significantly higher boost of 5.40 GHz. That explains the Ryzen's single-thread PassMark win: its boost clock is over a gigahertz higher, which helps in lightly threaded tasks that can sustain high frequencies.

Memory support is where the EPYC pulls far ahead. The EPYC supports DDR5 over a twelve-channel memory bus with a bandwidth of 576.0 GB/s. The Ryzen also supports DDR5 but over a dual-channel bus, yielding 83.2 GB/s. That is a 6.9x difference in theoretical memory bandwidth, which directly impacts the EPYC's leads in data compression and extended instructions. The EPYC also supports ECC memory; the Ryzen does not.

PCIe connectivity is another clear split. The EPYC offers Gen 5 with 128 lanes from the CPU, while the Ryzen offers Gen 5 with 28 lanes. The EPYC has no integrated graphics, as expected for a server part. The Ryzen includes a Radeon 610M iGPU. The EPYC uses the AMD Socket SP5, while the Ryzen uses the AMD Socket FL1. The EPYC is a server/workstation part with a locked multiplier; the Ryzen is a mobile part with an unlocked multiplier.

The Verdict

The data says the AMD EPYC 9135 is the superior processor in almost every benchmark category. It wins multi-core and single-core Cinebench tests by a consistent 15% margin. It wins PassMark physics by 152.6%, data compression by 9.1%, floating point by 7.9%, and integer math by 4%. Its average benchmark score is 82,980, which is 8.9% higher than the Ryzen's 76,212. For any workload that depends on sustained throughput, memory bandwidth, or heavy compute, the EPYC is the clear choice.

The Ryzen 9 8945HX has one meaningful advantage: single-threaded PassMark performance, where it leads by 6%. That is a real result, not an artifact. It also has a small win in data encryption (1.3%). But those are the only two categories in the entire benchmark set where the Ryzen comes out ahead. The Ryzen's higher boost clock of 5.40 GHz versus 4.30 GHz explains that single-thread edge, but it does not compensate for the EPYC's architectural and memory advantages.

The practical verdict depends on the use case. If the workload is server-side, data-heavy, or multi-threaded, the EPYC 9135 wins decisively. If the workload is a single-threaded task that can leverage a 5.40 GHz boost, the Ryzen 9 8945HX is competitive. But the overall score gap is large, and the EPYC's 96th percentile ranking versus the Ryzen's 95th confirms its higher standing. The EPYC is the better chip for most purposes, and the Ryzen is only preferable in narrow, single-threaded scenarios.

FAQ

Q: Which processor has better multi-core performance?

A: The AMD EPYC 9135 wins all three Cinebench multi-core tests (R15, R20, R23) by 15% each, scoring 4,952, 20,637, and 49,136 versus the Ryzen 9 8945HX's 4,305, 17,939, and 42,713.

Q: Is the Ryzen 9 8945HX faster in any test?

A: Yes, the Ryzen wins PassMark single-thread (3,907 vs 3,672, a 6% lead) and PassMark data encryption (40,836 vs 40,295, a 1.3% lead). Those are its only two wins out of 17 comparisons.

Q: How do the memory bandwidth figures compare?

A: The EPYC 9135 uses a twelve-channel memory bus with 576.0 GB/s bandwidth. The Ryzen 9 8945HX uses a dual-channel bus with 83.2 GB/s. That is a massive difference that affects memory-intensive tasks.

Q: Do both processors have the same core and thread count?

A: Yes, both have 16 cores and 32 threads. The EPYC also has 64 MB of shared L3 cache, same as the Ryzen, but the EPYC has 80 KB of L1 per core versus 64 KB per core on the Ryzen.

Q: What is the clock speed difference?

A: The EPYC 9135 has a base clock of 3.65 GHz and a boost of 4.30 GHz. The Ryzen 9 8945HX has a base of 2.50 GHz and a boost of 5.40 GHz. The Ryzen's higher boost helps its single-thread PassMark score.

Q: Which chip has a higher overall benchmark average?

A: The EPYC 9135 averages 82,980 across all benchmarks, while the Ryzen 9 8945HX averages 76,212. The EPYC also ranks at the 96th percentile versus the Ryzen's 95th.

Where Each One Wins

The AMD EPYC 9135 is the winner for any workload that stresses multiple cores or memory bandwidth. Its 15% Cinebench multi-core lead across all three versions of the test means it is the better choice for rendering, compilation, or any heavily threaded compute job. The PassMark physics result (5,477 vs 2,168, a 152.6% win) is the standout, indicating a massive advantage in simulation or physics-based workloads. The 576.0 GB/s memory bandwidth versus 83.2 GB/s makes the EPYC the obvious pick for data compression, database work, or any task that streams large amounts of data. Its 128 PCIe Gen 5 lanes also make it far more suitable for a workstation with multiple GPUs or NVMe drives.

The AMD Ryzen 9 8945HX is the winner in two narrow categories. Its 6% lead in PassMark single-thread (3,907 vs 3,672) means it is slightly better for lightly threaded applications that can hit its 5.40 GHz boost clock. Its 1.3% win in data encryption (40,836 vs 40,295) is marginal but real. For a mobile part with a 55W TDP versus the EPYC's 200W TDP, the Ryzen is also far more power-efficient, though the benchmark data does not include power consumption measurements. The Ryzen is the better choice if you need a single-threaded performer in a mobile form factor, but the EPYC dominates everywhere else.

Specification Differences

The two processors differ in nearly every key specification except core count and thread count. The EPYC 9135 uses Zen 5 architecture on a 4 nm TSMC process, while the Ryzen 9 8945HX uses Zen 4 on a 5 nm TSMC process. The EPYC has 16,630 million transistors on a 2x 70.6 mm² die; the Ryzen has 13,140 million on a 2x 71 mm² die. The EPYC's base clock is 3.65 GHz versus 2.50 GHz, but the Ryzen's boost clock is 5.40 GHz versus 4.30 GHz. The EPYC has 80 KB of L1 per core, the Ryzen has 64 KB. Both have 1 MB L2 per core and 64 MB L3. The EPYC supports twelve-channel DDR5 with 576.0 GB/s bandwidth and ECC memory; the Ryzen supports dual-channel DDR5 with 83.2 GB/s and no ECC. The EPYC has 128 PCIe Gen 5 lanes, the Ryzen has 28. The EPYC has no iGPU, while the Ryzen includes Radeon 610M. The EPYC uses Socket SP5, the Ryzen uses Socket FL1. The EPYC has a locked multiplier, the Ryzen is unlocked. The EPYC's launch MSRP is $1214; the Ryzen has no recorded launch MSRP. The EPYC was released in October 2024, the Ryzen in April 2025. The EPYC's TDP is 200W, the Ryzen's is 55W.