ähmmm… nope… the “normal streamer” does not record raw-data ( uncompressed 4K ) , instead they record already h.264,265,… or what ever files ( often eg. the nvidia encorder is used ). High quality for that youtube worst-re-render-advertising-platform is already 100mbit and that can an old HDD handle. Also a 4K raw stream is may be 2-3GB/s ( I remember more about, without recalc, about 12Gbit (b vs B ) ) and that can PCI3 also do.