AMD Does Not Believe Its Mobility Processors Require PCIe 4.0 Right Now


AMD has been the darling of the technology sector for quite a while now, pushing the envelope for technological advancement ever forward, but it looks like the company feels that its next-generation Ryzen 4000 mobility processors do not require PCIe 4.0 right now and will keep that particular platform at PCIe 3.0. This is interesting because Ryzen 4000 series processors, while being on the 7nm process, also do not contain Navi graphics as far as the GPU IP goes.

AMD: Ryzen 4000 series mobility processors will not support PCIe 4.0

The interview was conducted by Japenese publication and was attended by AMD's Scott Stankard (Senior Product Manager, Client Business Unit). AMD has been aggressively pushing PCIe 4.0 on its desktop side of things and this is one of the biggest selling points of its Zen 2 based processors right now. It was, therefore, eyebrow-raising, to see AMD not use PCIe 4.0 on its mobility side of things as well and give a response that seems very synonymous to the ones Intel gave for not pushing technology envelopes.

Here is a translation of the pertinent part of the interview that I was able to get from a friend:

Interviewer: The Zen 2 generation desktop platform adopted PCI Express (PCIe) 4.0 as one of its features. What about Ryzen 4000 (series procesosrs) for notebook PCs?

Scott Stankard: [Ryzen 4000 series] is compatible with PCIe 3.0. This is because in our judgement there aren't many scenarios [on the notebook side of things] that are able to adequately utilize PCI 4.0.

AMD is, of course, correct in their statement that there aren't many situations in a mobility environment that would necessitate the use of PCIe 4.0, but this has never stopped the company before. In fact, the fact that Ryzen 4000 mobility processors feature PCIe 3.0 along with the older Vega IP in their GPU (instead of the newer Navi IP) looks more and more like the company has somewhat compromised as far as mobility goes. This might not be a bad thing as far as sales and market shares go (because it would allow a lower ASP and broader adoption) but is certainly enough to raise eyebrows in enthusiasts.

Online specifications of the Ryzen 7 4800H "Renoir" APU list PCIe 3.0 as the adopted standard.

The company also confirmed in the same interview that the APU's SmartShift technology does not support synchronous capability and that users will not be able to run the iGPU and a dedicated Radeon GPU simultaneously. This is something that could have raised the value proposition of all-AMD builds exponentially (a laptop that featured an AMD CPU, AMD iGPU, and AMD dGPU, with the latter two running in sync would be a much powerful build than one with any other combination in the same budget).

Interviewer: Can "AMD SmartShift" support simultaneous operation of both iGPU and dGPU, dynamically distributing power between the iGPU and dGPU dpending on graphics processing load?

Scott Stankard: No, iGPU can dGPU cannot operate simultaneously. When one is working, the other is turned off completely.

That said, AMD's Ryzen 4800H processors are going to be extremely disruptive to the mobility market as these are one of the first processors shipping on a sub 14/10nm process. Since AMD will be able to tap into the cost and power savings of the 7nm process while having access to a much larger supply than Intel's 10th generation mobility processors, it should be able to achieve much higher economies of scale. If they stick to their usual pricing policy we should also see AMD laptops ship for about a $100 cheaper than other configurations of a similar power envelope. The cost of gaming, it would appear, is on its way down with every passing day.