AMD Ryzen 7 8840U vs AMD Ryzen 5 8640U

AMD Ryzen 7 8840U

The Ryzen 7 8840U is a powerful laptop processor (APU) of the Hawk Point family. This isn't an entirely new APU; instead, the R7 8840U is a rebadged R7 7840U with virtually no differences between the two to report. Its eight Zen 4 cores run at 3.3 GHz to 5.1 GHz and are SMT-enabled for a total of 16 processing threads. The great Radeon 780M iGPU is responsible for 3D processing and similar duties; the 8840U also features Ryzen AI, now in its 2nd generation, which is AMD's answer to Intel's GNA and DL Boost technologies.

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 more powerful than ever before.

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 deliver a double-digit IPC improvement over the former.

Elsewhere, the 8840U has 16 MB of L3 cache and support for super-fast DDR5-5600 and LPDDR5x-7500 RAM. The chip is compatible with USB 4 and thus with Thunderbolt. It comes with 20 PCIe 4 lanes, giving fast NVMe SSD up to 7.8 GB/s of throughput.

Systems built around the 8840U are designed to run 64-bit Windows 11, 64-bit Windows 10, or Linux. Please note that this processor is not overclockable and neither is it user-replaceable. It gets soldered to the motherboard for good instead (FP7, FP7r2, FP8 socket interfaces).

Performance

Since the 8840U is a 7840U in disguise, it's safe to expect it to be about as fast as the Core i7-12650H, as far as multi-thread performance is concerned. This means the chip is fast enough to make 99% of consumers happy, as of December 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 has 12 CUs (768 shaders) purring away at up to 2,700 MHz. This is exactly the right iGPU for people looking for a bit more horsepower than what Intel's aging Xe options can provide. The Radeon will let you use up to 4 monitors with resolutions as high as SUHD 4320p and it will also HW-decode and HW-encode the most widely used video codecs (including AV1, HEVC and AVC) without breaking a sweat. In terms of gaming, the thing is good enough for 1080p and medium-to-low settings, as of late 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 28 W. Laptop makers are free to change that value significantly, with values as low as 15 W and as high as 30 W greenlighted by AMD. Either way, an active cooling solution is a must for any system powered by this chip.

The 8840U is built with TSMC's 4 nm process for high, as of late 2023, energy efficiency.

AMD Ryzen 5 8640U

The Ryzen 5 8640U is a Hawk Point family processor that was unveiled in Q4 2023. This is not a new chip; instead, it's a rebadged Ryzen 5 7640U that we are dealing with here. Just like the 7640U, the R5 8640U 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.

Furthermore, this Ryzen 5 series laptop chip comes with the 2nd generation Ryzen AI technology.

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 said 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, is slated to bring a double-digit IPC improvement over the former.

Elsewhere, the 8640U 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 H2 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 8640U is neither overclockable nor user-replaceable. It gets soldered down for good (FP7, FP7r2, FP8 socket interfaces).

Performance

It's safe to expect the chip to be at least 10% faster than the Zen 3 Plus-powered Ryzen 5 6600U (6 cores, 12 threads, up to 4.5 GHz).

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. This iGPU will happily drive up to 4 monitors with resolutions as high as SUHD 4320p and it also will HW-decode and HW-encode AV1, HEVC, AVC without breaking a sweat. VP9 videos can be decoded but not encoded. As far as gaming is concerned, the average 760M in our database is reasonably close to the GeForce MX550 and the Radeon 680M. In early 2024, this means the latest games can only be played at 1600x900 with most settings set to Low.

Power consumption

The 8640U has a long-term power limit (default TDP) of 28 W that laptop makers are free to change to anything between 15 W and 30 W. Either way, an active cooling solution is a must for any system powered by the chip.

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