If the PS5 is consuming 200W at this point you would need to be at least 10x more efficiënt to consider a portable console. With 5nm they could scale power consumption with the same power 30%. That would mean (considering not just apu but also other components could require less) around 140W for the same performance. When apple will move to 3nm or 4nm for the 2022 iPhone it would free up a lot of current 5nm space that AMD can use. Late 2022 a ps5 slim would be possible on this node.
3nm uses another 30% less power for the same performance. So a ps5 of 100W would be possible on that node. Maybe the total package could reach 70W with some architectural improvements and improvements on chipset, storage ram etc. Still not enough for a portable console. They would need to cut that by 2/3 meaning you gotta make concessions like with the Series S.
So although possible to make a 1080p handheld in 2 to 3 years it would change the strategy completely. That seems unlikely. In 5-6 years from now It should be possible.
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