ethomaz said: There are 32MB Flash memory too for what I don't know yet The OS didn't run over the 256MB DDR3... this RAM is used only for the background tasks made by the ARM processor.

I guess the PS4 is more of a gaming consoles than the WII U is LOL.  

That my guesses now but the OS uses 2-cores of the x86_64 CPU and over 2.0GB of the GDDR5.

The ARM + 256MB is used for background download, video record, stream, etc...

look under  Genesys logic on the list and tell me what you see .

We don't have the numbers from sony to confirm. Afterall the PS3 used something like 40MB for it's OS.

Not possible.  

In the PS3, the PS2 EE existed ONLY for backward compatibility and was not accessible from a native PS3 program whatsoever so it could not be used for PS3 software in any way.  

Same with the Z80 in the Gameboy Advance for backward compatibility with Gameboy games, it wasn't accessible by the ARM7 and in fact is completely disabled in GBA mode to conserve power.

The PS2 however was pretty ingenious in that the IOP or IO coprocessor is a R3000 MIPs core (same as the PS1) that is an essential component of the PS2 as a true coprocessor to the R5900 EE, responsible for running independent modules (.IRX) that handled all IO for controller, memory cards, hard drive, network, optical drive, motion picture decompression etc, but was also built to capable of running native PS1 executables in PS1 compatibility mode. It is an R3000 core with MDEC, etc just like the PS1.   Since it was an essential part of the PS2 itself when not running in PS1 native mode, it could never ever be removed.

Not sure this was ever used for increasing performance of games though; previous poster was probably thinking about the two vector coprocessors VU0 and VU1.  Specifically VU0 which was often underutilized in macromode or not at all since it’s capabilities were much less than VU1.

That's what I was about to say!

The insiders misunderstood the NDA for "secret sauce"... it was not related to Xbone but just for Sony didn't show all the hourses behind PS4

Who do we need?MORE POWER!!!!

the PS3 had 512MB ram in total(256MB cpu/main ram + 256MB gpu ram), the amount "256" isn't in any form tied to the PS3

Gaikai means just receiving a video stream to your TV and sending an input stream to the server farm where the emulation is done, the unit at home doesn't need to emulate anything in that system, it only needs to decode/visualize the video and send out the input data

The PS3 used even over 100 MB for it's OS after the launch. The OS footprint was reduced over the years: http://community.eu.playstation.com/t5/PlayStation-3-General-Discussion/PS3-OS-memory-footprint-slashed/td-p/9874872

I expect similar OS-optimizations for the PS4, XBO, WiiU, 3DS and Vita i the next years.