It's probably not going to much more powerful than the Xbox one X if it wants to stay competitively priced.
A certain first party developer already mentioned to his environment to have access to dev kits. It will be a modified ryzen apu with navi gpu on 7mm. Gpu alone is around 10TF
There will be 16GB ram available up to 24 (undecided due to ram prices )
Release frame is end of 2019 to 2020.
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