turbochad69I mean it's pretty impressive that they packed what's essentially a whole x86 laptop + battery into something that small, I'd imagine it took some innovating
It's basically a slightly downclocked Ryzen 3 PRO 4450U/5300U (that's the closest equivalent) with a newer and slightly bigger GPU part (8 CU 1 year old RDNA 2 instead of 5/6 CU 4 year old GCN 5/Vega). It's still a 2 year old Zen 2.
It's sort of a spiritual successor to a bog standard Ryzen 5 3500U. That came out in 2019, with 2 year old Zen 1 4c/8t CPU, 2 year old 8 CU Vega GPU, 15W. So in 2021 you'd get a 2 year old Zen 2 4c/8t CPU, 2 year old 8 CU RDNA GPU. Really the only reason this isn't a list part is that AMD is for some reason still using Vega in their APUs, both for Zen 2 and Zen 3. So Valve needed a semi-custom part to get anything newer than Vega and at that point you might as well get the newest GPU architecture, RDNA 2, not RDNA. They stuck with Zen 2 for some reason though. Probably because it's cheaper.
EDIT: Better comparison: Literally take the Xbox Series S/X or PS5 chip. Cut the CPU in half. Cut the GPU by 2/3 (Series S) to 9/10 (Series X). Cut the bandwidth by 2/3 to 9/10, same as the GPU. There's your Steam Deck chip. Valve literally went to AMD with a console, pointed at it, and said "Give us that, but with a lot less power".
tl;dr
Valve's "innovation" is ordering a very standard semi-custom 15W APU from AMD, that only differs from what you can get in a standard notebook by having a newer GPU part.
The Good:
-It will run literally anything. Anything that runs on a pc should run on this.
-It's a lot more powerful than a Nintendo Switch. 5 times, maybe? That's just a guesstimate. Also more reasonable CPU to GPU ratio. 4 instead of 6 cores + 50% more GPU power seems like a much better deal than the 4500U in the AYA NEO
The Bad:
-It's still a low power mobile APU. While it can run any AAA title it will not run anything recent well. Not even at 1280x800. The GPU is about 1/3 of a 5300(M), literally the lowest-end GPU AMD is still selling. Think RX 550 or GT 1030. The 80$ GPUs from 4 years ago.
-64 GB eMMC is pretty fucking painful, both in terms of size and speed (mostly random access), 130$ for a 256 GB NVMe SSD is bloody robbery, about 3 times what Valve probably pays for it, same thing with 250$ for a 512 GB "high-speed" NVMe SSD