Of all places, shouldn't people here realize that the Connectix VPC angle is a dubious proposition for Xbox x86 emulation? Seriously, it's no secret that VPC (while great at enabling basic PC functionality) sucks up far too much resources to even hope to do x86-based videogames.
Well, maybe it could happen, but my hunch is to exercise extreme pessimism toward the possibility. We're talkin'bout VPC here- demanding videogames have clearly not been its domain.
Not true at all. Given sufficiently faster hardware, emulation is a fine solution.
Yeah, obviously if it is "sufficient", then it must be enough. Problem is, what is "sufficient", and is "sufficient" "plausible" for an XBox2 CPU. Also, please do recall that the current VPC is based around the emulation of an "old school" Pentium Pro CPU. For VPC to come up to PIII class processor compliance, would need to pull off a licensing miracle and possibly a substantial rewrite of VPC to model the new processor (likely a higher class processor will demand even more resources to emulate properly, thus making the "sufficient" criteria even higher). It's certainly not out of the realm of capability for if they really wanted it, but there is a nontrivial effort involved, and it isn't just a matter of getting "sufficient" clockrate to pull it off.
(...and since when has it been that MS gets censored when "$" is used for an "S"? Geez, have we gone a bit too "PC" here. I don't know if pun was intended or not.)
*evidently 3 smilies will signify reference to "Microsoft" in this post
Let's not forget that the obvious slam dunk solution to backwards compatibility here is that by 2005, the die size of a PIII could be so tiny, it would be a no brainer to just literally put one on-die somewhere in Xbox2 silicon (I dunno, use it as an I/O controller, for instance ).
but microsoft could use connectix just long enough to ensure backward compatibility of xbox games in xbox2, and then get rid of them once xbox2 reaches critical mass. But I imagine they will delay VPC for g5s for a while. (or maybe speed up the development since it has 2 uses.
But I imagine in the future gaming on a mac will be much better since xbox game developers (and playstation and gamecube) will not need to do much more ton port ir to os x....or some else could develop a virtual playstation/ xbox software to run the games. Maybe Microsofts real goal for connectix is to make a playstation killer by using chips with similar architecture and xbox 2 could have tha ability to run playstation games! No need for a playstation if an xbox will do both.
And the emulation would be a one trick pony. One set of hardware (the Xbox) and one defined set of apps (games).
Any interest in the PPC CPUs is a good thing. If Nokia would use them in their phones it would be good but having MS using it in the Xbox is far better That is very close to a desktop CPU. How could IBM avoid to hone their skills in making desktop CPUs?
Also, please do recall that the current VPC is based around the emulation of an "old school" Pentium Pro CPU. For VPC to come up to PIII class processor compliance, would need to pull off a licensing miracle and possibly a substantial rewrite of VPC to model the new processor (likely a higher class processor will demand even more resources to emulate properly, thus making the "sufficient" criteria even higher). It's certainly not out of the realm of capability for if they really wanted it, but there is a nontrivial effort involved, and it isn't just a matter of getting "sufficient" clockrate to pull it off.
The difference between Pentium Pro and Pentium III is SSE, and AltiVec is more than capable of efficient SSE emulation (4x the registers, more capable instruction set). No licensing required, no extensive re-write.
The ability to do it in software isn't in question, the motivation to do it is.
What I meant is that MS would have to license the PIII architecture, as I had thought was the case with Connectix and the Pentium Pro. Otherwise, I have no idea why their software would only encompass just Pentium Pro class functionality to this day. I just thought it was an "affordable" license due to the processor's age.
I don't feel SSE would be particularly difficult to emulate, either, but I had thought there would be at least a few minor architectural differences between a Pentium Pro and a PIII. I never imagined they would be mirror image CPU's with the exception of SSE and how the L2 cache is setup.
What I meant is that MS would have to license the PIII architecture, as I had thought was the case with Connectix and the Pentium Pro. Otherwise, I have no idea why their software would only encompass just Pentium Pro class functionality to this day. I just thought it was an "affordable" license due to the processor's age.
I don't feel SSE would be particularly difficult to emulate, either, but I had thought there would be at least a few minor architectural differences between a Pentium Pro and a PIII. I never imagined they would be mirror image CPU's with the exception of SSE and how the L2 cache is setup.
PPro, PII, PIII were all basically the same core. PII added MMX and brought the L2 on-chip (rather than 2 chips in one plastic case). PIII added SSE.
I'm not aware of any licensing Connectix had to emulate the x86, they just built their software to look like a PPro and have all the same instructions & registers. Since relatively little software uses SSE, and much of their market doesn't have AltiVec, they just never bothered to update the execution model to include MMX & SSE. If MS were to need a PowerPC-based PIII emulator, enhancing VPC would be relatively straightforward.
In an interesting side note, MS's Xbox product manager Robbie Bach dodges the question about software binary compatability between Xbox and Xbox2 in an interview with Germanys leading newsmag "Der Spiegel" (Link ).
Q: This means, games bought today will run on the new console?
A: This are details we'll have to work out. But even after the launch of the second generation Xbox, Microsoft will develop games for the old Xbox - so people will continue to enjoy it.
WRT to Intel's stake in the XBox - Intel doesn't really make much money at all from their processor sales related to the XBox. How IBM fares is another matter, and is largely subject to how well the XBox2 does.
In terms of backward compatibility, by the time they release the XBox2, they shouldn't have any problems emulating the 733MHz P3 that currently exists in the XBox, the trick is just to get all of the graphic routines passed to the GPU. I suppose they could pull a Sony and integrate the XBox silicon into some other component of XBox2. Either way, it shouldn't be an insurmountable problem, even with the switch in ISA.
WRT to DirectX and OSX - there is little relationship between getting DirectX to work on PPC, and porting it to OSX. While the former might be a stepping stone to the latter, there is no reason to believe that this is going to be the case, or that somehow XBox games will easily be ported to Apple hardware as a result.
Comments
Originally posted by Kickaha
Care to explain why not?
I could, but then I'd have to kill you.
Originally posted by Randycat99
Of all places, shouldn't people here realize that the Connectix VPC angle is a dubious proposition for Xbox x86 emulation? Seriously, it's no secret that VPC (while great at enabling basic PC functionality) sucks up far too much resources to even hope to do x86-based videogames.
Well, maybe it could happen, but my hunch is to exercise extreme pessimism toward the possibility. We're talkin'bout VPC here- demanding videogames have clearly not been its domain.
Not true at all. Given sufficiently faster hardware, emulation is a fine solution.
(...and since when has it been that MS gets censored when "$" is used for an "S"? Geez, have we gone a bit too "PC" here. I don't know if pun was intended or not.)
*evidently 3 smilies will signify reference to "Microsoft" in this post
Let's not forget that the obvious slam dunk solution to backwards compatibility here is that by 2005, the die size of a PIII could be so tiny, it would be a no brainer to just literally put one on-die somewhere in Xbox2 silicon (I dunno, use it as an I/O controller, for instance
But I imagine in the future gaming on a mac will be much better since xbox game developers (and playstation and gamecube) will not need to do much more ton port ir to os x....or some else could develop a virtual playstation/ xbox software to run the games. Maybe Microsofts real goal for connectix is to make a playstation killer by using chips with similar architecture and xbox 2 could have tha ability to run playstation games! No need for a playstation if an xbox will do both.
Originally posted by Programmer
Not true at all. Given sufficiently faster hardware, emulation is a fine solution.
Right, VPC uses to sucks in 3 D due to the emulation of the GPU.
Microsoft will use the video acceleration of the Xbox2 unlike VPC on macs.
The performance hit for video will be minimal, and emulating an old P3 733 on a PPC with the current of the G5 would not be a big deal.
Microsoft, have all the keys to be able to do a correct emulation of one of their olds products.
Any interest in the PPC CPUs is a good thing. If Nokia would use them in their phones it would be good but having MS using it in the Xbox is far better
Originally posted by Randycat99
Also, please do recall that the current VPC is based around the emulation of an "old school" Pentium Pro CPU. For VPC to come up to PIII class processor compliance,
The difference between Pentium Pro and Pentium III is SSE, and AltiVec is more than capable of efficient SSE emulation (4x the registers, more capable instruction set). No licensing required, no extensive re-write.
The ability to do it in software isn't in question, the motivation to do it is.
I don't feel SSE would be particularly difficult to emulate, either, but I had thought there would be at least a few minor architectural differences between a Pentium Pro and a PIII. I never imagined they would be mirror image CPU's with the exception of SSE and how the L2 cache is setup.
Originally posted by Randycat99
What I meant is that MS would have to license the PIII architecture, as I had thought was the case with Connectix and the Pentium Pro. Otherwise, I have no idea why their software would only encompass just Pentium Pro class functionality to this day. I just thought it was an "affordable" license due to the processor's age.
I don't feel SSE would be particularly difficult to emulate, either, but I had thought there would be at least a few minor architectural differences between a Pentium Pro and a PIII. I never imagined they would be mirror image CPU's with the exception of SSE and how the L2 cache is setup.
PPro, PII, PIII were all basically the same core. PII added MMX and brought the L2 on-chip (rather than 2 chips in one plastic case). PIII added SSE.
I'm not aware of any licensing Connectix had to emulate the x86, they just built their software to look like a PPro and have all the same instructions & registers. Since relatively little software uses SSE, and much of their market doesn't have AltiVec, they just never bothered to update the execution model to include MMX & SSE. If MS were to need a PowerPC-based PIII emulator, enhancing VPC would be relatively straightforward.
Q: This means, games bought today will run on the new console?
A: This are details we'll have to work out. But even after the launch of the second generation Xbox, Microsoft will develop games for the old Xbox - so people will continue to enjoy it.
MS's idea of backwards compatibility will be an XBox2 that neatly stacks on top of your existing Xbox1.
(just joking, people- loosen up)
WRT to Intel's stake in the XBox - Intel doesn't really make much money at all from their processor sales related to the XBox. How IBM fares is another matter, and is largely subject to how well the XBox2 does.
In terms of backward compatibility, by the time they release the XBox2, they shouldn't have any problems emulating the 733MHz P3 that currently exists in the XBox, the trick is just to get all of the graphic routines passed to the GPU. I suppose they could pull a Sony and integrate the XBox silicon into some other component of XBox2. Either way, it shouldn't be an insurmountable problem, even with the switch in ISA.
WRT to DirectX and OSX - there is little relationship between getting DirectX to work on PPC, and porting it to OSX. While the former might be a stepping stone to the latter, there is no reason to believe that this is going to be the case, or that somehow XBox games will easily be ported to Apple hardware as a result.
Originally posted by Randycat99
A quick joke:
MS's idea of backwards compatibility will be an XBox2 that neatly stacks on top of your existing Xbox1.
Heh. Either that or one fits inside of the other!