The OG Steam Deck (7nm, comparable to the Series S) has a die size of ~162mm2. In there, it packs an 4 core, 8 threads CPU and a 8 CU GPU.
On the other hand, the Xbox Series S packs an 8 core 16 threads CPU with 20CU GPU of the same architecture in ~197mm2 die.
This is a technical question, how come the Series S packs much more in just 25% more size? I’m not saying the Steam Deck should be as powerful as a Series S (that’d never happen, the power constraints would not make it possible), but I wonder if the CPU in the Series S is cut-back or if there’s anything in the Steam Deck’s SoC that could have been removed to get a lower cost.
It’s the memory controller and cache subsystem. Series S talks directly to gddr6 and doesn’t need nearly as much die space as all the L3 and big DDR5 memory controllers as the Ryzen APU in the steam deck.