AMD Ryzen 5 8640HS vs Intel Core i9-13905H vs AMD Ryzen 5 8645HS

AMD Ryzen 5 8640HS

The Ryzen 5 8640HS is a mid-range, Hawk Point family processor that was unveiled in Q4 2023. The 8640HS isn't actually a new chip; instead, it's a rebadged Ryzen 5 7640U, with slightly higher wattage of the 8640HS being the only meaningful difference between the two. The 8640HS has 6 SMT-enabled cores (12 threads) running at 3.5 GHz to 4.9 GHz. Those Zen 4 architecture cores are mated to the Radeon 760M integrated graphics adapter, and the Ryzen AI technology, now in its 2nd generation, is onboard as well to make apps like DaVinci Resolve and Adobe Photoshop more powerful than ever before.

Architecture & Features

Hawk Point chips are powered by the Zen 4 architecture, much like Phoenix and Dragon Range family chips are. That's not to say there is no difference between the three. With Hawk Point, AMD is betting big on generative AI; these processors are set to deliver an up to 40% increase in generative AI performance over 7040 series APUs.

Unlike Zen 3, Zen 4 features AVX512 support and, thanks to a plethora of other improvements including larger caches/registers/buffers, is slated to deliver a double-digit IPC improvement over the former.

Elsewhere, the 8640HS has 16 MB of L3 cache and USB 4 support (therefore, Thunderbolt is supported as well). The chip is compatible with DDR5-5600 and LPDDR5x-7500 RAM which is still impressive as of late 2023.

A system powered by this Ryzen 5 will have access to twenty PCIe 4 lanes; this means a speedy enough NVMe SSD will be able to deliver speeds up to 7.8 GB/s.

Systems powered by this APU are expected to run 64-bit Windows 11, 64-bit Windows 10, or Linux. Like most laptop chips, the 8640HS is neither overclockable nor user-replaceable. It gets soldered to the motherboard for good (FP7, FP7r2, FP8 socket interfaces).

Performance

It's safe to expect the APU to be at least 15% faster than the Zen 3 Plus-powered Ryzen 5 6600U (6 cores, 12 threads, up to 4.5 GHz), as far as multi-thread performance is concerned.

Your mileage may vary depending on how high the CPU power limits are and how competent the cooling solution of your laptop is.

Graphics

The Radeon 760M has 8 CUs (512 shaders) running at up to 2,600 MHz. While not great for gaming (unless you are fine with resolutions such as 900p and low detail settings), the iGPU will let you use up to 4 monitors with resolutions as high as SUHD 4320p. It also HW-decodes and HW-encodes the most widely used video codecs including AV1, HEVC, AVC without breaking a sweat.

Power consumption

The 8640HS has a long-term power limit (default TDP) of 28 W that laptop makers are free to change to anything between 20 W and 30 W. Most companies will probably go for a higher value to get better performance. Either way, an active cooling solution is a must for any system powered by the chip.

Last but not the least, the 8640HS is manufactured on TSMC's 4 nm process for high, as of late 2023, energy efficiency.

Intel Core i9-13905H

The Intel Core i9-13905H is a high-end mobile CPU for laptops based on the Raptor Lake-H series (Alder Lake architecture). It was announced in early 2023 and offers 6 performance cores (P-cores, Golden Cove architecture) and 8 efficient cores (E-cores, Gracemont architecture). The P-cores support Hyper-Threading leading to 20 supported threads when combined with the E-cores. The clock rate ranges from 2.6 to 5.4 GHz (single core turbo, all-core 4.9 GHz) on the performance cluster and 1.9 to 4.1 GHz on the efficiency cluster. The performance of the E-cores should be similar to old Skylake cores (compare with the Core i7-6920HQ). All cores can use up to 24 MB L3 cache. Similar to the i9-13900H but without vPro support and the 13905H uses a different package and socket.

Performance

Thanks to the high core count and high clock speed, the Core i9-13905H is (together with the 13900HK) the fastest 45W CPU for laptops and only bested by Raptor Lake-HX based models with more cores and improved P-cores (e.g., the i9-13980HX). Still, the CPU is very well suited for all demanding use cases like gaming, content creation, and scientific calculations.

Features

The integrated memory controller supports various memory types up to DDR5-5200 (up from 4800 MHz for the 12th gen). The Thread Director (in hardware) can support the operating system to decide which thread to use on the performance or efficient cores for the best performance. For AI tasks, the CPU also integrates GNA 3.0 and DL Boost (via AVX2). Quick Sync in version 8 is the same as in the Rocket Lake CPUs and supports MPEG-2, AVC, VC-1 decode, JPEG, VP8 decode, VP9, HEVC, and AV1 decode in hardware. The CPU now supports PCIe 5.0 x8 for a GPU and two PCIe 4.0 x4 for SSDs.

The integrated graphics card is based on the Xe-architecture and offers 96 EUs (Execution Units) .

The CPU is rated at 45 W base power (115 W PL2) but most laptops will use a PL1 of around 60 Watt. The SoC is manufactured in a 10nm process at Intel, which is known as Intel 7 (improved over the 12th Gen).

AMD Ryzen 5 8645HS

The Ryzen 5 8645HS is an upper mid-range processor (APU) of the Hawk Point family. This isn't an entirely new chip; instead, the 8645HS is a rebadged Ryzen 5 7640HS. The 8645HS was brought to life in Q4 2023 and it has 6 SMT-enabled Zen 4 cores (12 threads) running at 4.3 GHz to 5.0 GHz. The Radeon 760M iGPU is responsible for carrying out 3D calculations and similar duties, and the Ryzen AI tech is now in its 2nd generation.

Architecture & Features

Hawk Point family chips are powered by the Zen 4 architecture, much like Phoenix and Dragon Range family chips are. That's not to say there is no difference between the three. With Hawk Point, AMD is betting big on generative AI; these chips are promised to deliver an up to 40% increase in generative AI performance over 7040 series APUs making apps like DaVinci Resolve and Adobe Photoshop even more powerful.

Unlike Zen 3, Zen 4 features AVX512 support and, thanks to a plethora of other improvements including larger caches/registers/buffers across the board, is slated to bring a double-digit IPC improvement over the former.

Elsewhere, the 8645HS has 16 MB of L3 cache and a super-fast DDR5-5600 / LPDDR5x-7500 RAM controller. USB 4 (and thus Thunderbolt) is supported natively and so is PCIe 4. In fact, 20 PCIe 4 lanes are on offer; data transfer speeds of up to 7.8 GB/s will be possible provided a sufficiently fast NVMe SSD is used.

Systems powered by this Ryzen 5 series chip are expected to run 64-bit Windows 11, 64-bit Windows 10, or Linux. Please note that the APU is not overclockable and neither will you be able to replace it with a faster one as it gets soldered to the motherboard permanently (FP7, FP7r2, FP8 socket interfaces).

Performance

Since the 8645HX is an 7640HS in disguise, it is safe to expect the APU to be about as fast as the Ryzen 9 5900HX, Ryzen 7 6800H, Ryzen 7 7736U and also the Core i5-12500H, as far as multi-thread performance is concerned.

Your mileage may vary depending on how high the CPU power limits are and how competent the cooling solution of your system is.

Graphics

The Radeon 760M has 8 CUs (512 shaders) running at up to 2,600 MHz. While this is not the best graphics adapter for gaming as it's only just fast enough for low quality settings and resolutions such as 1600 x 900, it will let you connect up to four SUHD 4320p monitors and it also HW-encodes and HW-decodes the most widely used video codecs such as AV1, HEVC and AVC without breaking a sweat.

Power consumption

The 8645HS has a long-term power limit (default TDP) of 35 W to 54 W, giving laptop makers a choice between improving battery life and giving the system they are working on more oomph. Either way, an active cooling solution is a must for any system powered by the chip.

This Ryzen 5 series APU is built with TSMC's 4 nm process for high, as of late 2023, energy efficiency.