Xbox Backwards Compatibilty Explained

[Nacster]

Hardware issues will prevent use of existing games..Apparently according to the article it sounds like the new Xbox 360 will not technically be backwards compatible:

http://news.spong.com/detail/news.asp?prid=8741

[Headhunter]

Don't particularly trust that site, but their logic makes sense.

I figured that Microsoft would put out an emulator of some sort, or just put a "Oops, sorry" kind of warning with the console. I guess putting in a stripped down nVidia GPU is too pricey...

[CodecX81]

Which is too bad.
Halo 2 all accelerated probably wouldn't do that weird rendering draw thing in the cinematics.

Backwards compatibility.. every gamers dream, every manufacturer's nightmare.

[sleepyguy]

NVIDIA > ATI wrapper is too difficult i think to have 100% compatibility... meh... I'll be using XBOX1 for sometime anyway. I've played through maybe 1/3 of my games :)

[guest10586]

That backwards compatibility is garbage... You have to get new games that a recompiled. Yeah, like 2 copies of Halo 2 are going to do me any good. They might as well rerelease it with enhanced graphics.

[jerryhussain]

That backwards compatibility is garbage... You have to get new games that a recompiled. Yeah, like 2 copies of Halo 2 are going to do me any good. They might as well rerelease it with enhanced graphics.


No, you do not need to recompile your Xbox games

Ok, lets stop this right now. There is some serious wrong information floating around, so I need to clear this up. I grabbed my favorite PR dudes, and they are saying what I was telling a few of you in email:

Were not sure where this came from, and is incorrect. At launch, Xbox 360 will be backward compatible with the top Xbox games. Our goal is to have every Xbox game work on Xbox 360. You will NOT need to purchase a new version  your original games will work on Xbox 360.

http://majornelson.com/

[guest10586]

No, you do not need to recompile your Xbox games

Ok, lets stop this right now. There is some serious wrong information floating around, so I need to clear this up. I grabbed my favorite PR dudes, and they are saying what I was telling a few of you in email:

Were not sure where this came from, and is incorrect. At launch, Xbox 360 will be backward compatible with the top Xbox games. Our goal is to have every Xbox game work on Xbox 360. You will NOT need to purchase a new version  your original games will work on Xbox 360.

http://majornelson.com/


Your source seems extreamly bias to say the least...

[jerryhussain]

Your source seems extreamly bias to say the least...
Biased or not, GameSpot squashed the "recompiling" rumor in their latest rumor control. GamesIndustry.biz has been spreading many such rumors lately.

[guest10586]

Biased or not, GameSpot squashed the "recompiling" rumor in their latest rumor control. GamesIndustry.biz has been spreading many such rumors lately.

source?

[jerryhussain]

source?
http://gamespot.com/news/2005/05/20/news_6126204.html

Look how Gamespot takes repeated shots at GamesIndustry.biz for spreading these false rumors.

[eliteblaze]

major nelson works for xbox.com...

[BoxsterS]

Microsoft, themselves, said that Xbox 360 would be backward compatible for a large majority of the games during their press conference. The suggestion that games needed to be recompiled is just plain silly and the inherent ignorance of this statement says a lot for the person that first mentioned this and the people that continue to propagate it. The emulation will likely be software or a combination of hardware and software. Any Nvidia specific operations will be processed by an ATI wrapper.

The Xbox 360 and ATI GPU can easily emulate an Xbox via software emulation alone. The reason why Microsoft didn't promise 100% backwards compatibility is because some developers deviated form the Xbox best practices development guidelines and they know this. If Xbox games are bypassing Xbox API's and hitting the hardware directly, then compatibility is the responsibility of the developer, not Microsoft.

[toalan]

I would think that Nvida would put up a stink if their GPU would be emulated in the new XBOX 360. I can see that if you are doing it via software then maybe technically MS can avoid a lawsuit, but either way Nvida will put up a stink.

I do not know if XBOX 360 has the Horse Power to run xbox games without any special recompilation or patch, unless microsoft initially designed the xbox 360 with compatability in mind.

[toalan]

I guess a good indication of Xbox 360s ability to software emulate XBOX can be seen with MAC software for windows emulation. Basically you are using a PowerPC architechture to emulate an intel architechture, I think today at best you can run windows at the speed of maybe a P3 500, so P3 700 Mhz of XBOX should be easily achievable with the XBOX 360 CPU, but you also gotta emulate the GPU ontop of that so my guess is that at best the XBOX 360 would be barely able to fully software emulate XBOX. If you threw in some hardware then it should be no problem, but I do not think that MS will be able to implement anything on a hardware level for Nvida emulation or Nvida would sue. SO my guess is this, XBOX CPU emulation would be a combo of hardware and software, the XBOX GPU would be only software.

[BoxsterS]

I would think that Nvida would put up a stink if their GPU would be emulated in the new XBOX 360. I can see that if you are doing it via software then maybe technically MS can avoid a lawsuit, but either way Nvida will put up a stink.

I do not know if XBOX 360 has the Horse Power to run xbox games without any special recompilation or patch, unless microsoft initially designed the xbox 360 with compatability in mind.

Who said anything about emulating the Nvidia GPU? Xbox games use directX to render graphics. All calls to the directX API will now be handled by the ATI GPU that will perform that exact same function - this is called abstraction and as long as you use the API your dependency on the type of hardware used becomes irrelevant. Do PC games developed using the directX API (and what PC game isn't nowadays) care about whether you have an Nvidia or ATI graphics card? Of course not, as long as your graphics card and drivers support the directX specification than the game should run fine.

The problem with this Xbox backward compatibility issue is that we have people, who know nothing about software engineering or development, trying to fathom how it's going to work. They should stick to what they do best and review console games and not try and figure out how their games work.

[BoxsterS]

I guess a good indication of Xbox 360s ability to software emulate XBOX can be seen with MAC software for windows emulation. Basically you are using a PowerPC architechture to emulate an intel architechture, I think today at best you can run windows at the speed of maybe a P3 500, so P3 700 Mhz of XBOX should be easily achievable with the XBOX 360 CPU, but you also gotta emulate the GPU ontop of that so my guess is that at best the XBOX 360 would be barely able to fully software emulate XBOX. If you threw in some hardware then it should be no problem, but I do not think that MS will be able to implement anything on a hardware level for Nvida emulation or Nvida would sue. SO my guess is this, XBOX CPU emulation would be a combo of hardware and software, the XBOX GPU would be only software.

No it's not a good indication. The Xbox 360 has a PowerPC chip with 3 CPU cores, each running at 3.2 Ghz, which you neglected to take into condsideration. Are you telling my a 3 core CPU would have trouble emulating a 700 Mhz Intel CPU? As for the GPU issue, I think I've already explained the procedure that will be used.

[toalan]

I am gonna take the 3 cores with a grain of salt. I have no experience with anything that has more than 1 core, AMD or intel has yet to release a real dual core processor to the masses yet. But I agree that on paper the XBOX 360 will have the ability to emulate a P3 700. My only experience with anything a resembles more than 1 core is hyperthreading and it really was not all that it was hyped up to be. 3 cores could mean alot of things, maybe not all 3 cores are equal.

I am sure MS implemented a directx like API for graphics but since it never had to deal with compatability with other GPUs maybe they cut some corners and let the developers direct access to the hardware for some things. I mean abstraction is nice and all if you are looking for consistentcy across many platforms but when you only have 1 target platform maybe consistency gives way to practicality.

If the XBOX was so Directx compliant and therefore as easy to develop for as a PC title, it begs the question why only a few PC titles are ported over to XBOX, the one thing xbox lacks is quality RPGs something that PCs seem to have an abundance of. If you look at a game like DOOM3 which was released by ID for PC, it took ID like 8 months to release the xbox version and even then they had to get another developer to do the work.

[Nacster]

An article from gamesradar states that the XBOX 360 may not play all Xbox games and that the full compatability issue is in doubt..Below I have copied and pasted the article and included the actual Link below:

[23/05/05 12:33]
Full backwards compatibility in doubt

While Microsoft has said that Xbox 360 will be capable of playing 'top' titles for the original Xbox, the next-gen machine may not be fully backwards compatible, it has emerged.

"At launch, Xbox 360 will be backwards compatible with the top Xbox games," wrote Xbox Live boss Larry Hryb on his blog recently.

However, Hryb doesn't go as far as to say that all Xbox games will work on Xbox 360, saying only that this is Microsoft's "goal".

"Our goal is to have every Xbox game work on Xbox 360. You will not need to purchase a new 'version' - your original games will work on Xbox 360."

The problem seems to be that Xbox 360 will run an Xbox emulator as opposed to running Xbox games off embedded hardware, which means that some games could catch out the emulator - and hence wouldn't work.

We'll bring you further details and clarification on this as soon as we have it.


http://gamesradar.msn.co.uk/news/default.asp?pagetypeid=2&articleid=35991&subsectionid=1586

[JayPatel]

From TeamXBOX

Now that it's been announced at E3, I can finally reveal that the Xbox 360 feature I work on is... Xbox backwards compatibility!

With those words, Michael Brundage, a software engineer at Microsoft, kicked off this week’s update on his blog, finally revealing his latest assignment at the Xbox division. He first discusses the project and explains why it is so special:

Xbox backwards compatibility is a unique project in so many ways, and I feel very fortunate to get to work on it. I'm sure it will be the hardest technical challenge of my career -- I can't imagine what could possibly top it in terms of sheer technical difficulty.

Then Brundage explains why the project represents such a challenge from a technical perspective:

For example, some people observe the CPU and GPU architectures are utterly different between the Xbox 360 and the Xbox, and then speculate about the difficulties those differences pose for emulation. Without really understanding anything that's involved, they're already convinced that backwards compatibility is a difficult task.

Lastly, Brundage paints a more detailed picture of what it will take to make backward compatibility a reality:

Finallly, there are a very few people who understand both Xbox systems inside and out to an expert level of detail that I'm not about to go into here. They perform more sophisticated calculations using the Art of Software Engineering, but ultimately reach the same conclusions as those not skilled in the Art: Backwards compatibility is impossible. One such skeptic interviewed me for my current job, and pointedly asked during the interview how I planned to handle the project's certain future cancellation. And yet, here it is. It's magic!

This is part of what makes working at Microsoft so much fun -- the opportunity to work on magical projects and do the impossible. It's a lot of hard work, of course, but the challenge makes it fun.

We'll have more on Xbox backward compatibility as it becomes available.

[_pOtEnZa_]

with nintendoi announcing free dl for the nes, snes and n64 system and sony announcing it will play games from ps2 and ps1 i dont know how microsoft, witch released there xbox the last of the 3 and now coming out the quicket cant even make their machine compatible, that just plain sucks, i guess ill use it as a dvd player lol

[Nacster]

An interesting article on the MICROSOFT compatability issues and Pricing for the Xbox 360:

http://biz.gamedaily.com/features.asp?article_id=9761&filter=