AMD Ryzen 7 5825U vs AMD Ryzen 5 8640HS vs AMD Ryzen 7 8845HS

AMD Ryzen 7 5825U

The AMD Ryzen 7 5825U is a processor for thin and light laptops based on the Cezanne generation. It is part of the "Barcelo" refresh in early 2022 and offers 100 MHz higher clocked CPU cores compared to the old Ryzen 7 5800U. The R7 5825U integrates all eight cores based on the Zen 3 microarchitecture and is the fastest U-series processor at launch. They are clocked at 2 (guaranteed base clock) to 4.5 GHz (Turbo) and support SMT / Hyperthreading (16 threads). The chip is manufactured on the modern 7 nm TSMC process.

The new Zen 3 microarchitecture offers a significantly higher IPC (instructions per clock) compared to Zen 2. For desktop processors AMD claims 19 percent on average and in applications reviews showed around 12% gains at the same clock speed.

Performance

The average 5825U in our database is in the same league as the Ryzen 7 7735U and the Core i7-1270P, as far as multi-thread benchmark scores are concerned. Which is a really good result, as of early 2023.

Thanks to its decent cooling solution and a long-term CPU power limit of 37 W, the 2022 Envy x360 15 is among the fastest laptops built around the 5825U that we know of. It can be more than 15% faster in CPU-bound workloads than the slowest system featuring the same chip in our database, as of August 2023.

In addition to the eight CPU cores, the APU also integrates a Radeon RX Vega 8 GPU with 8 CUs at up to 2000 MHz. The dual channel memory controller supports DDR4-3200 and energy efficient LPDDR4-4266 RAM. Furthermore, 16 MB level 3 cache (up from 8 MB at the 4800U) can be found on the chip.

The TDP of the APU is specified at 15 Watt (default) and can be configured from 10 to 25 Watt by the laptop vendor (most chips are configured higher than 15 Watt). That means the chip is intended for thin and light laptops (but with fans).

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 a slightly higher wattage as well as higher clock speeds on the Ryzen AI NPU. 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.

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.

AMD Ryzen 7 8845HS

The Ryzen 7 8845HS is a powerful Hawk Point family chip that we believe to be a Ryzen 7 7840HS in disguise but with higher clock speeds on the Ryzen AI NPU. The R7 8845HS was brought to life in H2 2023; it features 8 cores (16 threads thanks to SMT support) running at up to 5.1 GHz. Last but not the least, the Radeon 780M serves as the integrated GPU.

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 that there is no difference between the three. With Hawk Point, AMD uncorks its 2nd generation Ryzen AI technology meaning the new processors are expected to deliver an up to 40% increase in generative AI performance over 7040 series APUs. Dozens of popular apps such as DaVinci Resolve support this technology, as of late 2023.

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 8845HS has 16 MB of L3 cache and a seriously fast RAM controller (up to LPDDR5x-7500 and up to DDR5-5600, ECC-enabled memory included). PCI-Express speeds are capped at 1.97 GB/s per lane which corresponds to the 4.0 spec.

This Ryzen 7 series chip is designed to run 64-bit Windows 11, 64-bit Windows 10 or Linux; please note that it isn't overclockable and neither is it user-replaceable. It gets soldered to the motherboard for good instead (FP7, FP7r2, FP8 socket interfaces).

Performance

Since the 8845HS is a 7840HS in disguise, it's safe to expect it to be just slightly faster than the Core i9-13900H and also the Ryzen 9 7940HS, as far as multi-thread performance is concerned. This is a very fast chip, as of Q3 2023.

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 780M (12 CUs / 768 shaders, up to 2,700 MHz) is capable of powering 4 monitors simultaneously with resolutions as high as SUHD 4320p. It will also have little issue hardware-encoding and hardware-decoding the most widely used video codecs (AV1, HEVC, AVC). As far as gaming is concerned, the thing will let you play most games at 1080p as long as you are fine with moderate quality settings. Long story short, this is the best iGPU money can buy, as of H2 2023.

Your mileage may vary depending on how high the CPU power limits are, how competent the cooling solution of your system is, how fast the RAM of your system is (there is no dedicated VRAM here).

Power consumption

This Ryzen 7 series chip has a long-term power limit (default TDP) of 35 W to 54 W, giving system makers a choice between improving battery life and making the system they're designing insanely fast. Either way, an active cooling solution is a must for a laptop or a mini-PC built around this APU.

The R7 8845HS is built with a 4 nm TSMC process for high, as of late 2023, energy efficiency.