Chinese tech news site mydrivers.com recently reviewed Lenovo's new Yoga Air 14s 2023 Ryzen Edition, featuring the Lenovo-exclusive AMD Ryzen 7 7840S CPU. That's an 8-core/16-thread Zen 4 chip, with a lower 30W TDP. The tech outlet revealed that the 7840S with a 30W TDP performs exceptionably well, landing just 5% below AMD's much more power-hungry 45W Ryzen 9 7940HS CPU.
The Ryzen 7 7840S and its little brother the Ryzen 5 7640S are not your traditional AMD Ryzen CPUs and shouldn't be confused with their "HS" series counterparts. What makes them special is that they both are made exclusively for Lenovo and are not purchasable by any other OEM (at least right now).
Compared to AMD's 7040HS-series CPUs, these "7040S" CPUs require less power and generation less heat, featuring a 30W TDP compared to the configurable 35-45W TDP on the 7040HS parts. The 7840S in particular features eight Zen 4 CPU cores with a clock speed of 3.30–5.10 GHz, Radeon 780M graphics, and AMD's 7040-series exclusive Ryzen AI chip for hardware-based AI acceleration. The 7840S built into the Yoga Air 14s 2023 Ryzen Edition also utilizes AMD's larger FP8 package that's designed to support high-performance interfaces such as AMD's MIPI SCI.
It remains a mystery why these chips are exclusive to Lenovo, but this is not the first time we've seen OEM-exclusive CPUs. MyDrivers tested the 7840S laptop in a number of different benchmarks, including all the Cinebenches, R15, R20, and R23, POV-Ray, X264, X265, a chess benchmark, and 3DMark.
Overall, the 7840S scored incredibly well, featuring just a 5% performance lower score than AMD's Ryzen 9 7940HS CPU that packs higher clock speeds and a 50% higher TDP. However, there are a few workloads (x264 and x265) where the gap was quite a bit larger.
Take these results with a dash of salt since we've only seen this laptop benchmarked by one reviewer so far. But if the benchmarks are accurate, the 7840S is a seriously power-efficient CPU that behaves similarly to AMD's Ryzen Z1 chip.
Lenovo isn't cheating either with a big beefy cooling solution and an extra thick chassis that might allow the chip to boost higher with extra low thermals. The Yoga 14s features a very thin 13.9mm chassis, close to what most other ultra-thin laptops utilize. Beyond the CPU, the Yoga 14s Ryzen Edition packs a lot of premium features, including a 14.5 inch 2944x1840 screen featuring a peak brightness of 600 nits, a variable refresh rate 90Hz screen, Dolby Vision support, Display HDR 500 support, and Eyesafe 2.0 protection.
It also packs an impressive 6-speaker audio system and a large 70Wh battery, which according to MyDrivers gets more than 14 hours of battery life. Storage and memory are about as good as it gets including 32GB of super speedy LPDDR5X 6400MHz RAM and a 1TB PCIe 4.0 PM9A1 Samsung SSD.
Lenovo has apparently made one of the most desirable Ryzen laptops on the market. Not only does it feature a lot of premium features, but the Lenovo-exclusive Ryzen 7 7840S packs an impressive amount of firepower in such a small package — enough firepower to compete with AMD's significantly higher wattage Ryzen 9 units.