AMD Ryzen 9 7945HX vs AMD Ryzen 9 7945HX3D Comparison

The AMD Ryzen 9 7945HX and AMD Ryzen 9 7945HX3D are near-identical twins separated by a single, decisive feature. The benchmark data shows the 3D V-Cache model wins 16 of 25 head-to-head tests, but the standard 7945HX is far from obsolete, taking 9 wins in specific workloads. The overall average benchmark scores are essentially a tie — the 7945HX posts 56802 against the 7945HX3D’s 56635, a mere 0.3% difference. The choice is not about overall speed; it is about which workload profile matters more to the user. The 7945HX3D dominates in physics simulation and prime number calculations, while the 7945HX leads in raw multi-threaded throughput and certain math operations.

Where Each One Wins

The 7945HX3D is the specialist, and its specialty is latency-sensitive and physics-heavy tasks. Its most dramatic victory is in the PassMark physics test, where it scores 4321 against the 7945HX’s 2500 — a commanding 42.1% lead. Similarly, in PassMark find prime numbers, the 3D model scores 446 versus 284, a 36.3% advantage. These are workloads where the enlarged L3 cache reduces memory access delays, allowing the cores to stay fed with data. The 3D model also sweeps the entire Cinebench suite, winning R15, R20, and R23 in both single-core and multi-core runs by a consistent 5% margin. This consistency suggests the 3D V-Cache helps in sustained rendering tasks, not just synthetic physics.

The standard 7945HX wins where raw compute throughput is king and cache size matters less. It takes the 3DMark max threads test with a score of 13612 against 12936, a 5.2% victory. It also leads in PassMark integer math (207524 vs 201217, a 3.1% edge) and floating point math (123390 vs 121619, a 1.5% lead). The 7945HX wins the 3DMark 16-thread test by 2.2% (12737 vs 12459) and narrowly takes the 4-thread test by 0.9%. These results indicate the standard chip’s higher base clock of 2.50 GHz versus 2.30 GHz gives it an edge in workloads that do not benefit from the extra cache but do respond to higher clock speeds. In data compression and encryption, the 7945HX also edges ahead by 1% and 0.8% respectively, showing a slight advantage in memory-bound but non-cache-sensitive tasks.

Architecture Differences

Both processors are built on the same foundational architecture: Zen 4 on the Dragon Range codename, fabricated on TSMC’s 5 nm process. They share the same 16 cores and 32 threads, the same dual-chiplet design with a die size of 2x 71 mm², and the same 55 W TDP. The differences begin with the cache hierarchy. The 7945HX has 64 MB of shared L3 cache, while the 7945HX3D adds a 1x 64MB 3D V-Cache slice, doubling the L3 total to 128 MB. This is the defining architectural change, and it explains the benchmark divergence. The transistor count reflects this addition: the 7945HX3D has 17,840 million transistors versus 13,140 million on the standard part.

The base clock is the other key difference. The 7945HX runs at 2.50 GHz, while the 7945HX3D drops to 2.30 GHz. Both boost to the same 5.40 GHz, and both have the same 64 KB L1 per core and 1 MB L2 per core. The 3D V-Cache model also has a later release date — July 2023 versus January 2023 — but the production status remains active for both. Memory support is identical: DDR5, dual-channel, 83.2 GB/s bandwidth, with ECC support. Both have the same Radeon 610M integrated graphics, Gen 5 PCIe with 28 lanes, and use the AMD Socket FL1. The multiplier is unlocked on both, allowing overclocking, though the 3D V-Cache’s thermal characteristics may limit headroom in practice.

Head-to-Head Benchmarks

The single biggest win for the 7945HX3D is in PassMark physics, where the 42.1% delta is not a marginal improvement but a category shift. The score of 4321 versus 2500 shows the 3D V-Cache has a transformative effect on physics calculations, likely because these workloads repeatedly access a working set that fits within the 128 MB L3 but exceeds the 64 MB L3. The second-largest win is PassMark find prime numbers, with a 36.3% delta (446 vs 284), reinforcing the cache-latency advantage. The 3D model also wins the PassMark multithread test by 5.1% (57476 vs 54548), which is notable because the standard 7945HX wins other multi-threaded tests.

The 7945HX’s largest wins are smaller in magnitude. Its 5.2% lead in 3DMark max threads (13612 vs 12936) is its biggest margin, followed by 3.1% in PassMark integer math. The 3.6% deficit in Geekbench multicore (16156 vs 16758) shows the 3D model also has an advantage in general-purpose multi-core performance. In single-core tests, the results are nearly identical: Geekbench single-core is a tie at 2769, while 3DMark single-thread and PassMark single-thread go to the 3D model by 1.2% and 0.2% respectively. The Cinebench R15/R20/R23 results are uniform 5% wins for the 3D model across the board, suggesting the cache helps in both single and multi-core rendering scenarios. The 7945HX’s wins in data compression (1%), encryption (0.8%), and floating point (1.5%) are consistent but narrow, indicating that the standard chip retains a slight edge in pure ALU/FPU throughput.

FAQ

Q: Does the 7945HX3D have a higher average benchmark score than the 7945HX?

A: No. The 7945HX has a slightly higher average benchmark score of 56802, compared to the 7945HX3D’s 56635, a 0.3% difference in favor of the standard chip.

Q: Which processor is better for physics simulations?

A: The 7945HX3D is significantly better. It scores 4321 in PassMark physics, which is 42.1% higher than the 7945HX’s 2500.

Q: Are there any benchmarks where the two processors tie?

A: Yes. In Geekbench single-core, both score exactly 2769, resulting in a 0% delta. This is the only exact tie in the head-to-head data.

Q: Does the 7945HX3D have a lower base clock than the 7945HX?

A: Yes. The 7945HX3D has a base clock of 2.30 GHz, while the 7945HX has a base clock of 2.50 GHz. Both processors share the same 5.40 GHz boost clock.

Q: Which chip wins more head-to-head benchmarks?

A: The 7945HX3D wins 16 out of 25 benchmarks, while the 7945HX wins 9. However, the magnitude of the 7945HX3D’s wins is often larger, particularly in physics and prime number tests.

Q: Is the L3 cache size the only architectural difference?

A: No. The 7945HX has 64 MB of L3 cache, while the 7945HX3D has 128 MB total, achieved by adding a 1x 64MB 3D V-Cache slice. The transistor count also differs, with the 7945HX3D having 17,840 million versus 13,140 million on the standard part.

Specification Differences

The two processors differ in only four specification fields. The base clock is 2.50 GHz on the 7945HX versus 2.30 GHz on the 7945HX3D. The L3 cache is 64 MB shared on the standard part, versus 128 MB shared on the 3D part, which includes a 1x 64MB V-Cache slice. Transistor count increases from 13,140 million to 17,840 million. The release date also differs: the 7945HX was released on 2023-01-03, while the 7945HX3D was released on 2023-07-26. All other fields — cores, threads, boost clock, TDP, socket, architecture, process node, die size, L1/L2 cache, memory support, memory bandwidth, ECC, PCIe, integrated graphics, market segment, production status, and multiplier unlock — are identical.

The Verdict

The data presents a clear split. The AMD Ryzen 9 7945HX3D is the better choice for users whose workloads are dominated by physics simulation, prime number calculations, and general multi-threaded rendering. Its 42.1% lead in PassMark physics and 36.3% lead in prime numbers are decisive, and its clean sweep of the Cinebench suite by 5% in every test shows consistent rendering superiority. The 3D V-Cache’s 128 MB L3 is a genuine advantage in these scenarios, and the lower 2.30 GHz base clock does not appear to harm it in sustained workloads.

The AMD Ryzen 9 7945HX is the better choice for users who prioritize raw multi-threaded throughput in specific workloads. It wins the 3DMark max threads test by 5.2% and leads in integer math by 3.1% and floating point math by 1.5%. Its higher 2.50 GHz base clock gives it an edge in tasks that do not fit into the L3 cache or that are sensitive to clock speed rather than cache latency. The 7945HX also wins data compression and encryption, making it slightly better for those specific server-like tasks.

The overall average benchmark scores are within 0.3% of each other, meaning there is no universal winner. The 7945HX3D wins more tests (16 vs 9), but many of the 7945HX’s wins are in high-throughput math operations. Users needing the best physics and rendering performance should pick the 7945HX3D. Users needing the best integer and floating point throughput in a mobile form factor should pick the standard 7945HX. Both are in the 94th percentile of all CPUs, and both are active production parts. The decision rests entirely on workload profile, not on overall capability.