I think MS will use it,but it will for sure be customize. We don't know what agreement is between SONY and AMD. I think is not about royality, more about some design choices that are gonna be custom and exclussive for PS5. Sony won't tell you right now, its too early, but for sure they didn't co-developed and co-found the NAVI for free.
They already basically told us what's custom about the chip. The big thing will be dedicated audio on the chip and maybe if they want to push it some units dedicated to RT. I don't expect anything more of it.
Also, why would custom choices be exclusive for Sony? If MS also goes with the same chip they can have anything that's within the realm of possibility. People are reading way too much into "customization" and "co-development". It can mean anything from huge changes to just dictating clock speeds.
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