Most of the things you are mentioning here directly tie into what gives us the raw/compressed figures. 12 channel... so the raw data speed of PS5 is much higher than XSX.... 9 ryzen vs 4 equivalent, which is why the compressed figures on PS5 are so much higher...
This is just breaking down why the PS5 figures are higher, it's not something separate.
No you oversimplifying it and omiting specs. Like not even mentioning the 4 PCIE4.0 laned with direct acces from the apu to the ssd. The PS% is suposed to stream data directly from the SSD and from ram at the same time while also suposed to use the ssd as ram and some are speculating that the ps5 can run the OS and other background task bypasssing the ram cmpletly and reserving all 16gb for graphics. Remains to be seenn though its all rumors and speculations.
The 12 chanel vs 8 or 4 channels ssd is another thing. While yes each chanel is a factor the overall speed, each chanel has a limited data cap wich directly afects tranfers. as data is split between each chanel, but if data is on the same chanel in goes in order so one has to wait for the other and in case that data is sensitive it need to waait for it and stops the transfer of the other lane. Thats one of the reasons storage usually dosent transfer data as the top speed advertise. Having 12 chanels means that there is less chance for that to happen and has the the ssd working more at top speed.
Yes the ryzen equivalent is more to do with how much more work needs to be done. AS far as im aware.
This guy explains it very simple and more in depth. ignore the click baity title of the video. he barely mentioned that.
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