AMD Ryzen 7 8745HX vs AMD Ryzen 9 7945HX Comparison

The benchmark data is unambiguous: the AMD Ryzen 9 7945HX is the superior processor in nearly every measurable workload, decisively outperforming the AMD Ryzen 7 8745HX. While both chips share the same Zen 4 architecture and 5 nm process node, the Ryzen 9’s doubled core count and larger cache create a performance gap that is consistently wide across all tested scenarios. The Ryzen 7 8745HX does not win a single head-to-head benchmark in the provided data, making the choice between them straightforward for users prioritizing raw performance.

Head-to-Head Benchmarks

The Ryzen 9 7945HX dominates the PassMark suite, winning all 11 recorded comparisons. The largest margins appear in compute-heavy tasks. In integer math, the Ryzen 9 scores 207,524 versus the Ryzen 7’s 100,328, a delta of -51.7% for the latter. Floating-point math tells a similar story: 123,390 for the Ryzen 9 against 61,972 for the Ryzen 7, a -49.8% difference. These results indicate that the 16-core Ryzen 9 is nearly twice as fast as the 8-core Ryzen 7 in pure arithmetic throughput.

Multithreaded performance is where the core count advantage becomes most apparent. The Ryzen 9’s PassMark multithread score of 54,548 eclipses the Ryzen 7’s 31,517, a -42.2% delta. This pattern repeats in data compression, where the Ryzen 9 hits 707,249 versus 363,759 (-48.6%), and in data encryption, with scores of 42,703 and 21,840 respectively (-48.9%). The Ryzen 9 also leads in extended instructions (51,834 vs 27,638, -46.7%) and random string sorting (81,736 vs 44,494, -45.6%).

The smallest gaps are found in single-threaded and physics workloads, but the Ryzen 9 still wins. In PassMark single-thread, the Ryzen 9 scores 4,040 against the Ryzen 7’s 3,879, a modest -4% delta. This shows that while the Ryzen 7’s higher base clock of 3.60 GHz helps close the gap, it cannot overcome the Ryzen 9’s higher boost clock of 5.40 GHz. The physics test shows a -32.8% difference (2,500 vs 1,681), and the prime number search yields a -44% delta (284 vs 159). Overall, the Ryzen 9’s average benchmark score of 60,099 is virtually identical to the Ryzen 7’s 60,104, with a deltaPct of 0, placing both at the 92nd percentile among all CPUs.

Architecture Differences

Both processors are built on the same Zen 4 architecture and use the 5 nm process from TSMC, but the physical implementation differs significantly. The Ryzen 9 7945HX is a dual-die design with a die size of 2x 71 mm² and a total of 13,140 million transistors. The Ryzen 7 8745HX is a single-die part with a 71 mm² die and 6,570 million transistors. This difference in silicon directly explains the core count disparity: the Ryzen 9 offers 16 cores and 32 threads, while the Ryzen 7 offers 8 cores and 16 threads.

Cache allocation is another major divider. Both chips feature 64 KB of L1 and 1 MB of L2 per core, but the shared L3 cache doubles from 32 MB on the Ryzen 7 to 64 MB on the Ryzen 9. This larger L3 pool is a key reason for the Ryzen 9’s superior performance in data-heavy tasks like compression and sorting, as it can hold more working data closer to the cores. The memory subsystem is identical: both support DDR5 with a dual-channel bus and 83.2 GB/s of bandwidth.

Clock speeds are the one area where the Ryzen 7 leads. The Ryzen 7 has a base clock of 3.60 GHz versus the Ryzen 9’s 2.50 GHz, but the Ryzen 9’s boost clock of 5.40 GHz tops the Ryzen 7’s 5.10 GHz. Both chips feature an unlocked multiplier, use the AMD Socket FL1, and are classified as mobile parts with a 55 W TDP. The integrated graphics are identical: Radeon 610M. A notable feature difference is ECC memory support, which is present on the Ryzen 9 but absent on the Ryzen 7.

FAQ

Q: Which CPU has more cores and threads?

A: The AMD Ryzen 9 7945HX has 16 cores and 32 threads, while the AMD Ryzen 7 8745HX has 8 cores and 16 threads.

Q: Is the Ryzen 7 8745HX faster in any benchmark?

A: No. In the provided head-to-head data, the Ryzen 9 7945HX wins all 11 benchmarks, including single-threaded tests where the Ryzen 7’s higher base clock is not enough to overcome the Ryzen 9’s higher boost clock.

Q: What is the difference in L3 cache size?

A: The Ryzen 7 8745HX has 32 MB of shared L3 cache, while the Ryzen 9 7945HX has 64 MB of shared L3 cache.

Q: Do both CPUs support ECC memory?

A: No. The Ryzen 9 7945HX supports ECC memory, but the Ryzen 7 8745HX does not.

Q: What are the clock speed differences?

A: The Ryzen 7 8745HX has a base clock of 3.60 GHz and a boost clock of 5.10 GHz. The Ryzen 9 7945HX has a base clock of 2.50 GHz and a boost clock of 5.40 GHz.

Q: Are these CPUs from the same generation?

A: No. The Ryzen 7 8745HX is from the 8000 series, while the Ryzen 9 7945HX is from the 7000 series, though both are based on the same Zen 4 (Dragon Range) architecture.

Specification Differences

• Series: AMD Ryzen 7 8745HX (8000 series) vs AMD Ryzen 9 7945HX (7000 series)
• Cores: 8 vs 16
• Threads: 16 vs 32
• Base Clock: 3.60 GHz vs 2.50 GHz
• Boost Clock: 5.10 GHz vs 5.40 GHz
• Transistors: 6,570 million vs 13,140 million
• Die Size: 71 mm² vs 2x 71 mm²
• L3 Cache: 32 MB (shared) vs 64 MB (shared)
• ECC Memory Support: No vs Yes
• Release Date: 2025-04-22 vs 2023-01-03
• Part Number: 100-000001851 vs 100-000000870

Where Each One Wins

Based on the benchmark results, the AMD Ryzen 9 7945HX is the clear winner in every category. Its advantages are most pronounced in multithreaded and data-intensive workloads. For users running video encoding, 3D rendering, scientific simulations, or any application that scales across many cores, the Ryzen 9’s 16 cores deliver roughly 42% to 52% more performance than the Ryzen 7 in integer math, floating-point math, and multithreaded tests. The larger 64 MB L3 cache also makes it the better choice for database work, file compression, and encryption tasks, where it outperforms the Ryzen 7 by margins between 44% and 49%.

The Ryzen 7 8745HX has no benchmark wins to claim, but its specifications suggest it is a more efficient single-die part. Its higher base clock of 3.60 GHz narrows the gap in single-threaded performance to just 4%, making it a viable option for lightly threaded tasks like web browsing or office productivity where the Ryzen 9’s extra cores are not utilized. However, since the Ryzen 7 does not win a single recorded test, its only theoretical advantage is a lower transistor count and smaller die footprint, which could translate to lower power consumption in some scenarios, though the TDP for both is listed as 55 W.

The Verdict

The data points to one conclusion: choose the AMD Ryzen 9 7945HX unless there is a specific reason to avoid its dual-die design. With an identical average benchmark score of 60,099 (vs 60,104 for the Ryzen 7) and a 92nd percentile ranking, the Ryzen 9 offers the same overall standing but with massively better peak performance. It is the only option for users who need maximum throughput in multithreaded applications, as it leads by roughly 32% to 52% in every compute-heavy test. The Ryzen 9’s support for ECC memory also makes it suitable for workstation-class tasks where data integrity is critical.

The Ryzen 7 8745HX is not a slow processor by any means, but it is strictly a lower-tier alternative in this comparison. Its single-die construction and fewer transistors suggest a simpler, potentially more power-efficient part, but the benchmark data does not support any performance advantage. For users who prioritize single-threaded speed, the difference is minimal (4%), and for everyone else, the Ryzen 9’s 16 cores are simply too dominant to ignore. The verdict is clear: the Ryzen 9 7945HX is the superior choice for almost all workloads, with the Ryzen 7 8745HX serving only as a cheaper or more compact alternative that sacrifices significant performance.