In May, AMD unveiled their Ryzen 7040U series of CPUs designed for thin and light notebooks, which they codenamed 'Phoenix.' Initially, AMD announced four Zen 4-based CPUs for the ultra-portable notebook market, with the Ryzen 7 7840U (8C/16T) and Ryzen 5 7640U (6C/12T) both leading the charge with AMD's integrated Ryzen AI, which is AMD's first-generation NPU for on-chip AI and inferencing.
Fast forward a few months, and AMD is unveiling an additional two new Ryzen 7040U series processors. But there's a twist: these chips are using their smaller and highly optimized Zen 4c cores. Although AMD's more petite Zen 4c core initially debuted with the launch of their EPYC 97x4 'Bergamo' processors for native cloud deployments, server chips were never going to be the only place AMD used their compact cores. Zen 4c was already silently released in the consumer market as part of the Ryzen Z1 (non-extreme) CPU used in ASUS's ROG Ally handheld (2x Zen 4 + 4x Zen 4c), and now Zen 4c is getting a proper welcome in the consumer market with its use in a set of Ryzen laptop chips.
The first of the two new Ryzen 7040U processors with Zen 4c is the Ryzen 5 7545U, which coincidentally shares similar specifications to the existing Ryzen 7540U processor. The critical difference is that the Ryzen 5 7545U uses two full-fat Zen 4 cores with four of the smaller Zen 4c cores, which is an interesting implementation, to say the least. The second is the Ryzen 3 7440U, a direct successor to the...well, processor with the same name, the Ryzen 3 7440U, which has the exact specifications, with the only difference coming in using three Zen 4c cores, with just one Zen 4 core.
There's some nuance to pick apart with AMD's decision to use Zen 4c within their mobile platforms, as AMD highlighted at the launch of Bergamo that the 'c' in Zen 4c stands for 'Cloud,' and it's interesting to see AMD opting to integrate Zen 4c in a primarily low-end consumer segment. There are very notable differences between Zen 4 and Zen 4c, which makes things interesting, to say the least, especially when comparing the two core architectures and their intended use cases.
