AMD Ryzen 9 7845HX vs AMD Ryzen 5 7645HX vs AMD Ryzen 9 7945HX3D

AMD Ryzen 9 7845HX

The AMD Ryzen 9 7845HX is a fast high-end laptop processor of the Dragon Range series. It offers 12 of the 16 cores based on the Zen 4 architecture that supports hyperthreading (24 threads). The cores clock from 3 (base) up to 5.2 GHz (single core boost). The 7845HX is the second-fastest mobile Ryzen CPU at launch and derived from the desktop Ryzen 9 7900X.

The Dragon Range series still uses a chiplet design with two CCD-clusters (each with 8 possible cores) in 5nm and an IO-die (including the memory controller and the Radeon 610M iGPU) in 6nm. The chip integrates 4x USB 3.2 Gen2 (10 Gbps) ports (no USB4), 28 PCIe 5.0 lanes (for GPU and SSDs) and a dual-channel DDR5-5200 memory controller.

Performance

The average 7845HX in our database is in the same league as the Core i9-13900HX, as far as multi-thread benchmark scores are concerned. This is a super-fast chip, as of mid 2023; of course, your mileage may vary depending on how competent the cooling solution of your laptop is and how high the CPU power limits are.

The R9 7845HX is rated at a TDP of 55 Watt and can be configured from 45 to 75 Watt (cTDP).

AMD Ryzen 5 7645HX

The AMD Ryzen 5 7645HX is a fast high-end laptop processor of the Dragon Range series. It offers 6 cores based on the Zen 4 architecture that supports hyperthreading (12 threads). The cores clock from 4 (base) up to 5 GHz (single core boost).

The performance of the R5 7645HX should be significantly higher than the fastest 6-core CPU of the Ryzen 6000 mobile series the Ryzen 5 6600H. Especially single threaded performance should be very good thanks to the new Zen 4 cores and relatively high clock speeds. This means even the old Ryzen 9 6980HX (also 5 GHz, but Zen 3) should be slightly slower in single threaded workloads.

The Dragon Range series still uses a chiplet design with two CCD-clusters (each with 8 possible cores, the 7645HX only uses one CCD with 6 of the 8 cores) in 5nm and an IO-die (including the memory controller and the Radeon 610M iGPU) in 6nm. The chip integrates 4x USB 3.2 Gen2 (10 Gbps) ports (no USB4), 28 PCIe 5.0 lanes (for GPU and SSDs) and a dual-channel DDR5-5200 memory controller.

The R5 7645HX is rated at a TDP of 55 Watt and can be configured up to 75 Watt (cTDP).

AMD Ryzen 9 7945HX3D

The AMD Ryzen 9 7945HX3D is a fast high-end laptop processor of the Dragon Range series. It offers 16 cores based on the Zen 4 architecture that supports hyperthreading (32 threads). The cores clock from 2.3 (base) up to 5.4 GHz (single core boost). Compared to the similar R9 7945HX, the 7945HX3D offers an additional 64 MB 3D V-Cache on one CCD-Cluster. This helps in some workloads that can use the additional fast cache (e.g. some games). The guaranteed base clock however was reduced from 2.5 to 2.3 GHz.

The performance of the R9 7945HX3D is similar to the R9 7945HX in workloads that wont make use of the bigger L3 cache. Most games however can use the additional memory. AMD e.g. was advertising the HX3D with 4% to 53% higher performance in 1080p high settings.

The Dragon Range series still uses a chiplet design with two CCD-clusters (each with 8 possible cores) in 5nm and an IO-die (including the memory controller and the Radeon 610M iGPU) in 6nm. The chip integrates 4x USB 3.2 Gen2 (10 Gbps) ports (no USB4), 28 PCIe 5.0 lanes (for GPU and SSDs) and a dual-channel DDR5-5200 memory controller.

The R9 7945HX3D is rated at a TDP of 55 Watt and can be configured up to 75 Watt (cTDP).