PS4 (also PS3 & 360) I run hdmi to my 43" 1080p led, but I also run optical audio to surround. I really only use the surround for mp and games that have stealth/survival sp as the extra sound is very helpful plus ambience is improved.
But if you have hdmi capable surround you don't need optical (or coaxial) audio obviously.
PS2 has optical audio too, and digital audio is possible for original Xbox if you have HD a/v pack (component + rca audio + optical audio).
https://gaminghistory101.files.wordp...xbox_hd_av.jpg
But my PS2 and Xbox aren't hooked up to my 1080p atm, I just have them in the spare room on a 32" trinitron (SD). I have another surround system in there that is pre-digital (actually an old Yamaha prologic system) so that audio can be converted from rca to simulated surround.