AMD Ryzen 9 7840HX vs AMD Ryzen 7 4800H

AMD Ryzen 9 7840HX

The chip also integrates 4x USB 3.2 Gen2 (10 Gbps) ports (no USB 4), 28 PCIe 5.0 lanes (for GPUs and SSDs), a dual-channel DDR5-5200 memory controller and a small AMD Radeon 610M graphics card (2CUs, 400 - 2200 MHz).

AMD Ryzen 7 4800H

The AMD Ryzen 7 4800H is a Renoir APU designed for larger, more powerful laptops with room for better termals. The Ryzen features eight Zen 2 cores running at 2.9 GHz (base clock speed) to 4.2 GHz (Boost). The CPU also has 8 MB of L3 cache and a Vega series integrated GPU. Thread-doubling SMT tech is enabled in this processor, allowing for up to 16 concurrent processing threads.

Architecture

Ryzen 7 4800H is manufactured on the modern 7 nm TSMC process and in part thanks to this fact AMD promises an up to 2x higher performance-per-watt figure compared to Ryzen 3000 series mobile APUs. This isn't the only noteworthy change however as Zen 2 architecture is leagues ahead of the outgoing Zen+ when it comes to single-core performance. Renoir family processors feature up to 8 CPU cores compared to 4 cores of the previous generation mobile AMD CPUs.

A 4800H will work with dual-channel DDR4-3200 or quad-channel LPDDR4-4266 RAM. The important difference between desktop Ryzen 4000 and mobile Ryzen 4000 processors is that the latter do not have PCI-Express 4.0 support, meaning those blazing-fast NVMe SSDs will be limited to a throughput of 3.9 GB/s.

The Ryzen 7 gets soldered straight to the motherboard (FP6 socket) and is thus not user-replaceable. Please go to our Renoir processor family hub for more information on these CPUs.

Performance

The average 4800H in our database is in the same league as the Core i7-11850H, the Core i7-1360P and also the Ryzen 7 PRO 6850U, as far as multi-thread benchmark scores are concerned. This highlights just how great of a job Renoir designers did, back in the day.

Thanks to its decent cooling solution and a long-term power limit of 45 W, the MSI Alpha 17 A4DEK is among the fastest laptops built around the 4800H that we know of. It can be more than 20% faster in CPU-bound workloads than the slowest system featuring the same chip in our database, as of August 2023.

Graphics

Ryzen 7 4800H features the Radeon RX Vega 7, a 7 CU integrated graphics adapter running at up to 1,600 MHz. The iGPU's underlying architecture is fairly old as of 2021, yet its 448 shaders will let you play many games of 2020 and 2021 as long as you stick to reasonable resolutions and presets. F1 2021 runs well at medium quality, 1080p resolution, to give you an example. A Vega 7 can be as fast as a GeForce GTX 1050 Max-Q, or as slow as an 80 EU Iris Xe; this depends on the benchmark as well as on cooling system performance and TDP settings of a laptop as mentioned above. As the iGPU has no VRAM of its own, it is paramount that fast system RAM is used.

The Vega definitely supports UHD 2160p monitors at 60 Hz. This iGPU is capable of hardware decoding AVC, HEVC and VP9-encoded videos. There is no AV1 support to be found here though. Such a video will have to be SW-decoded leading to much lower energy efficiency.

Power consumption

This Ryzen 7 series chip has a default TDP (also known as the long-term power limit) of 45 W. Laptop makers are allowed to change that to anything between 35 W and 54 W, with clock speeds and performance changing accordingly as a result. The Ryzen 7 4800HS is a 35 W edition of the Ryzen 7 4800H that trades away a bit of performance for lower power consumption. In both cases, an active cooling solution is a must.

Both the 4800H and the 4800HS are built with TSMC's 7 nm process for decent, as of late 2022, energy efficiency.