| larrysdirtydrawss said: .. i imagine lots will put the framebuffer in there.. wouldnt the framebuffer eat into a large chunk of the esram bw if stored in main ram? plus you gotta put everything else over 32MB into main ram also(wich i would image being a number of things given the game type for next gen) main charcters,vehicles,giant set pieces, bosses,mini bosses, detailed weapone ect ect, and all these very detailed things will also eat a lot of bw,it might be very risky putting the frame buffer in esram leaving little bw left over for the objects over 32mb.. also,is it impossible for the ps4 to up their clocks it the future like the psp? |
You can choose what to put into main ram and what to put into esram. As for textures, you use a feature called prt (partially resident textures), using the main ram as "reservoir" (instead of the hd, like pcs are doing it) and use the esram as "playground". The crossbar switch allows you to pump some memory area from esram (and main ram) to gpu and at the same time pump memory from main ram into the other part of esram. Also you can calculate how much time you lose if you simply fill the entire esram from main ram. (Assuming you can't daisy chain dmes), this takes only about 0.6milliseconds. For a 30fps game, that is negligible. There really is very sophisticated hardware circuitry involved in the XBox One to get around the esram space limitation. The problem is, of course, if you use any esram tricks you must program and track them. Even if you use the esram as framebuffer and call it a day, I'd say you could get pretty far.
Whether Sony can up their clock, who knows? They seem to run everything on a master clock of 800MHz (doubled to 1.6GHz for cpu) and it works... If the 1.75Ghz is correct and not a mistyped 1.705Ghz, then XBox One runs cpu and crossbar clocks independantly. If Sony upped the clock to say 900MHz, they would probably get into trouble with heat in the gpu (the cpu could easily clock at 1.8-2.0GHz without thermal problems). My guess is we might see a PS4.5 in 2 years around 1.9Ghz/950Mhz clocks, once the apu goes 20nm (maybe a PS4.75 with more CUs/TMUs in the gpu).
