jeff_rigby
Banned
You are technically correct but the idea is to emulate the processes (not emulate the processor) that take place in a PS3 on a PS4. If the process includes multiple loops on data and the instructions can fit into a SPU's cache it's blindingly fast. If the process is working on a very large data set a GPU can be setup to perform the process 30 times faster than a SPU can perform on the same data set. A combination of a modern X86-64 processor and a 400 core GPU used properly can come closer to real time simulating a Cell processor than ever before.There will be no realtime Cell emulation in 2013. Most likely there will not be any in 2020 either.
To do it you at the very very least need 7 cores clocked at 3.2 Ghz or higher that can do the same operations per clock that an SPE can, and offer the terabytes/s of local store bandwidth available on Cell. Just. Not. Happening. It is generally not possible to use a large number of simpler, slower "cores" to emulate a single fast core in real time.
The PS3 OS contains a number of known processes that use SPU code that could be simulated in real time using a PS4 APU or even discrete hardware. The PS3 OS used SPUs for DSP duty and with Sony stating that they are going with SOC it's not as much of a hit to have discrete hardware.
As you know Cell simulators have been available for years and modeling software that can model Cell functionality using multiple plugin models of for instance GPU parallel processors has been available since 2007, one was developed by Barcelona Supercomputer Center. BSC also developed the first Cell simulator for IBM. PS3 Backward Compatibility running on a different processor and different GPU is going to be incredibly difficult. Is it even possible, what memory processes are going to be needed, clock speeds for CPU and GPU etc? I don't know, I don't think Sony knows/knew but BSC has been doing comparisons, designing HPC systems using GPUs and has the Cell modeling software they developed. BSC is also publishing papers on improving cell software functionality as of Nov 2011 that could be included in future PS3 compilers.
There is a rumor that BSC is working on a Cell2 for a PS4. This could be a early rumor and no longer true or it could be that BSC is working on a PS3 Cell simulator for a PS4 and giving feedback to Sony on what hardware and memory systems would be needed to simulate a PS3 on a PS4. Or another possible, BSC could be working on the PS4 OS and design with PS3 BC not even a possible.
BC is an important feature and it can be accomplished by including a Cell processor in the PS4, by possibly including a few SPUs or it might be possible to simulate a PS3 using the APU and other hardware in a PS4 so that well behaved PS3 software works.
PS4 Developer kits would not need to have Cell processors included if they are only being used for BC which I think would be wasteful so unlikely and the APU can provide the same Cell general functionality 3-30? times faster if used properly so including cell is again wasteful.
If it is possible to simulate a PS3 on a PS4, this is something that developers with PS4 development kits would not NEED TO KNOW so it can't leak and since it's incredibly difficult to do, the ASSUMPTIONS are that there will be no BC.
The Xbox Durango is going to have Backward compatibility without much difficulty. It's extremely important that the PS4 have PS3 backward compatibility.