AMD announces Ryzen 7000U laptop CPUs with more efficient Zen 4c cores

AMD introduces its first laptop processors with a hybrid architecture. The company comes with two laptop chips that have both Zen 4 and Zen 4c cores. The Zen 4c cores are physically smaller, but otherwise virtually identical to the larger Zen 4 cores.

AMD will initially come with two Ryzen 7000 laptop processors that have Zen 4c cores. The AMD Ryzen 5 7545U gets two Zen 4 and four Zen 4c cores, for a total of six cores and twelve threads. The chip also has a total of 22MB cache, clock speeds of up to 4.9GHz and has a configurable TDP of 15 to 30W. This Ryzen 5 7545U will replace the existing Ryzen 5 7540U, with six regular Zen 4 cores. According to AMD, apart from the use of Zen 4c in the new variant, the chips are virtually identical. They offer the same maximum clock speeds, the same amount of cache and the same TDP range and should perform almost the same.

The AMD Ryzen 3 7440U has four cores and eight threads. That concern according to Anandtech one Zen 4 and three Zen 4c cores, although AMD did not concretely confirm this in a briefing with journalists. This chip has 12MB cache, clock speeds up to 4.7GHz and also a TDP of 15 to 30W.

Zen 4c is a modified variant of the existing Zen 4 architecture, AMD reports. Zen 4c cores are 35 percent smaller than regular Zen 4 cores and are optimized for performance per watt and core density. AMD says that Zen 4c has lower ‘absolute clock speed limits’ than the regular Zen 4 cores. Furthermore, the cores are identical. They support the same instruction sets, offer the same IPC and both support simultaneous multithreading, which means each core has two threads.

AMD’s Zen 4c cores are optimized for efficiency, performing best at low power consumption. The manufacturer shows benchmark results in Cinebench R23 at various TDPs. For example, under 15W, the Ryzen 5 7545U with Zen 4c cores performs slightly better than the 7540U with just regular Zen 4 cores. The 7540U performs slightly better above 20W. However, AMD reports that the performance differences will not or hardly be noticeable in practice.

AMD released its first Zen 4c chips for the server market earlier this year, in the form of EPYC Bergamo. In addition to being smaller in size, these server chips also had less L3 cache per core. Remarkably, AMD says during a briefing with journalists that the laptop chips with Zen 4c cores do have the same amount of cache as their counterparts with only Zen 4 cores. For example, the aforementioned Ryzen 5 7540U and the new 7545U both have 22MB cache.

The new AMD Ryzen 7000U laptop processors will be available ‘soon’. The manufacturer does not yet mention a concrete release date and does not mention any laptops in which these chips will appear.