*spin-off* Importance of Backward Compatibility Discussion

Nothing was needed to "give up".

MS already owned the license for Xcpu. The had/have the talent in-house to push that design beyond the 3 core 6 thread design currently in xb360.

Switching from this architecture to x86 gave us not much of a performance bump (any?), but it broke BC and I'm quite sure MS had to pay AMD for the design in xbone.

So the question is how much did it cost to switch from ppc to x86?

So you are saying the designers and engineers of the ps4 and xb1 are stupid because they could have built in BC for less than nothing? I suggest that notion is out of touch with reality.
 
Higher efficiency for sure.
OoOE is a win.
Larger caches is a win.
Prefetch is a win.
Branch prediction is a win.
The caches have multiple improvements beyond size, and the memory pipeline on Xenon is prone to some very problematic stalls.
Integer resources are doubled per-thread. (edit: correction, per core, so per-thread is likely 4x)
The memory controller is not on the far side of a physical or emulated front-side bus.
Power management is also a bonus for Jaguar, where Xenon and Cell were very primitive.

Many of these wins could be found in other ppc designs from IBM, but even without that, the existing design could be leveraged by having a larger cache (EDRAM) and more cores.
This is coupling more of one bad thing with a manufacturing headache, and potentially two silicon dead ends.
 
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70million+ Xbox 360 owners is not incentive? Wow!
What's the cost of creating your own cloud gaming platform from scratch, or buying OnLive and kitting it out to play XB360 games? Unless providing BC is guaranteed to win back all 70 million existing customers because that's the feature they value more than any other and that alone will prevent them from considering the competition, BC isn't worth 70 million XB1 customers. It's also a feature that doesn't generate revenue, unless you are reselling people the games they already bought. It's just not a profitable venture. Sony's intentions with Gaikai extended beyond just playing BC, which is why they spent $380 million on it. I very much doubt that stream PS3 games, if they ever really happen, will generate Sony much of that money; certainly not if people are playing the games they already bought instead of rebuying them Nintendo-style.

It's funny that the biggest face of disgust I get from talking with xbox gamers is the lack of BC.
What about the disgust at Sony for not providing BC?

I'd have to say that the Engineers at MS had to be aware of these issues in choosing jaguar right? They also had to have a pretty solid understanding of what performance to expect out of jaguar too.
And they also had a good undertanding of what BC is really worth to a platform and the did the math (same as Sony, this gen and next) and came to the conclusion that emulation is a hell of a lot of cost for very little gain.

But that avoids the real question. It isn’t how much the customer is willing to pay for this expected feature (at this point, it is expected).
XB360 wasn't really BC with XB. PS3 wasn't really BC with PS2 and 90% of PS3's sold don't have any BC. I don't know why you think console gamers expect BC.

The question is: how much is MS willing to lose for not including it?
About as much as Sony will lose for not including it. Which is firstly not very much, and secondly evened out by neither offering BC.

Higher efficiency for sure.
OoOE is a win.
Larger caches is a win.
Prefetch is a win.
Branch prediction is a win.

But the overall performance gain isn't an order of magnitude over xcpu.

Many of these wins could be found in other ppc designs from IBM, but even without that, the existing design could be leveraged by having a larger cache (EDRAM) and more cores.
At what cost to development effort and tools? You paint a very simple, naive view, and then back up your arguments with a lot of hostility towards MS despite Sony making the very same choices. Unless you regard them both as utterly incompetent, it's very apparent that BC is difficult and costly and not worth the bother when they evaluated the business propositions.
 
As a fellow xbox gamer, I would have much rather seen MS throw in a 12 core (24 thread) 3.2GHz xenon (it’s only a 4x increase in transistors) connected to a high bandwidth 64-128mb EDRAM (not 6T SRAM) (also accessible by the GPU for GPGPU).

No BC issues, and I’m quite sure the 8 core 1.6GHz jaguar would not be able to keep up with such a configuration.
Yes, it would. Jaguar has a huge real-world advantage over the XCPU. Don't mistake, for one minute, that because it can't match, clock for clock, extremely optimized code on the 360 that it won't massively outperform anything the 360 could do.

MS tested real games running on the 360, and they averaged out to 0.2 IPC per core, and that's when you include the heavily expensive and time consuming (to developers) optimised sections of the game.
If you compile the same piece of C code for Jaguar and Xenon, the Jaguar code will run twice as fast on average (actually around 2.5x, but for simplicity...). 3 jaguar cores are therefore twice as fast as the entire Xenon CPU in real world tasks. 6 cores would easily equal your 12 core space heater idea. The next gen consoles have 8.
Turns out, the jaguar cores are too weak to emulate xcpu.

Whoda thunk it? :p
Being too weak to emulate a CPU does not mean you are not much more powerful than that CPU for code actually written and compiled for it.
Thanks for going more in depth with the issues involved with BC.

I'd have to say that the Engineers at MS had to be aware of these issues in choosing jaguar right? They also had to have a pretty solid understanding of what performance to expect out of jaguar too.

Either that, or like many things at MS lately, it seems one hand didn't know what the other hand was doing.
In theory, dynamic recompilation can provide a good enough solution for the 90% case, but the question was the resources that would need to be dedicated to it. The solution would have had to be almost free for it to have been viable, and it was not. The product was originally planned as no BC, and some engineers were spun off to look at the possibility as a nice-to-have.

How about 0%?

How about dropping in a quad (or more) xcpu (12 core 24 thread)? Couple that with either larger caches, or a single large 64-128MB EDRAM pool to mitigate in-order execution stalls. Viola! BC and higher performance.
And no need to turn on your furnace in the winter, and no worries on getting realistic sounds in games involving fighter planes, the fan would provide them for you.
But the overall performance gain isn't an order of magnitude over xcpu.
Order of magnitude means 10x, so you are correct. However, your quad xenon solution is only 4x, which the new consoles easily exceed, while using far less power, generating far less heat, and costing developers less in development. And at 24 hardware threads, your solution would be extremely hard to keep working at optimum capacity.
 
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What about the disgust at Sony for not providing BC?

I don't know. Most of my friends are xbox gamers. Sorry?

And they also had a good undertanding of what BC is really worth to a platform and the did the math (same as Sony, this gen and next) and came to the conclusion that emulation is a hell of a lot of cost for very little gain.

I wouldn't be so sure on their powers to judge the market (either company really). There are a ton of examples which show that in fact, whatever math they did do, could use improving. ;)

XB360 wasn't really BC with XB. PS3 wasn't really BC with PS2 and 90% of PS3's sold don't have any BC. I don't know why you think console gamers expect BC.

It isn't so much that gamers expect BC. People in general expect it these days. Sorry, it's the age of ipad, iphone, ipod, galaxy tab, galaxy S, etc.

People expect their new gadgets to work with the stuff they already bought for their old gadget. And renaming the device "One" doesn't change that expectation.

About as much as Sony will lose for not including it. Which is firstly not very much, and secondly evened out by neither offering BC.

Granted.

But gamers (like me) who are not happy, lose nothing by PS4 not having BC with ps3.

The lack of BC just makes it that much easier to switch (either side).

It just so happens that Sony is offering a much more compelling gaming console this gen, so that is a win by default.

At what cost to development effort and tools?

XNA used to work quite well before they killed it. Cross architecture development saw pretty much any game on xb360 also land on pc (if the pub/dev chose to).

You paint a very simple, naive view, and then back up your arguments with a lot of hostility towards MS despite Sony making the very same choices.

Sony making the choice they made with ditching cell for x86 had a lot to do with devs having a very real problem with investing a lot of time to code for cell. That's Sony being proactive and listening to developers complaints.

Kudos.

Sony then followed this up with the purchase of Gaikai to support BC via ps3 servers.

Kudos.

It sucks that native BC isn't there, but Sony is making the best of the situation, and compensated this negative with a lot of positives.

$399 MSRP
1.8TF
8GB GDDR5
Less ram dedicated to non-game functionality
Included headset :p
More consumer and developer friendly policies/attitude

Unless you regard them both as utterly incompetent, it's very apparent that BC is difficult and costly and not worth the bother when they evaluated the business propositions.

As illustrated above, yes it sucks that they both dropped the ball on users purchases the past 8 years (BC), but that just leveled the playing field.

From there, Sony has just been playing better ball.
 
Plus no bc means less people playing 360 games = less outcry when they shut off the online servers

Given that MS didn't shut down the Live servers for the original Xbox until mid 2010. I doubt either way that that will be a problem.
 
It isn't so much that gamers expect BC. People in general expect it these days. Sorry, it's the age of ipad, iphone, ipod, galaxy tab, galaxy S, etc.
People expect devices they buy now to play everything. I doubt any of them realistically expect a console bought in 2005/2006 to play everything. Furthermore, early adopters are typically more clued up. Furthermore, early adopters are more likely to be console fans with past experience to know a console is a discrete platform (until that format changes).

It just so happens that Sony is offering a much more compelling gaming console this gen, so that is a win by default.
This isn't a versus thread. Can you please stop with the non-stop business comparison?

XNA used to work quite well before they killed it. Cross architecture development saw pretty much any game on xb360 also land on pc (if the pub/dev chose to).
XBA was not suitable for powering AAA titles. AFAIK only indie titles used XNA. MS are dropping XNA, so the only reason to go to the effort of porting it to XB1 is to enable indie titles. It'd be nice (bkilian says MS looked into it for added value) but it's not a trivial undertaking and the cost has to be weighed against the gains. Considering everything else gamers have to grumble about XB1, throwing money at BC for a few indie titles probably is just throwing money away.

Sony making the choice they made with ditching cell for x86 had a lot to do with devs having a very real problem with investing a lot of time to code for cell. That's Sony being proactive and listening to developers complaints.
Ms facing the same issues is just being stupid though?

Sony then followed this up with the purchase of Gaikai to support BC via ps3 servers.
BC has yet to be shown running on Gaikai. They 'hope' to get BC working on Gaikai. The end-user experience might be crap. At launch, PS4 is no better off than XB1, for exactly the same reasons - the CPU architecture was a dead end and couldn't be emulated and was too costly to throw in the box as a component.

From there, Sony has just been playing better ball.
Immaterial to the discussion. The question is what value BC adds to gamers and a new console.
 
Ahh, it was TheChefO. After his incessant bitching against Sony, now he's going to incessantly bitch about MS and turn everything into a goddam business discussion. Not on my watch!
 
Given that we know that Sony has had people working on a 22nm (I believe?) shrink of Cell, it's clear that Sony is spinning new silicon for another PS3 refresh.

I wonder how difficult it would be for Sony to throw a hardware h.264 encoder module into the next PS3 revision, and give it the ability to stream to PS4 and/or Vita out of the box? It'd sure be nice to be able to put a new super-super-super slim PS3 on my network and be able to play PS3 games on the PS4.

Presumably, Sony has to be doing something like this sort of hardware to be planning Gakai streaming of PS3 games next year, yes?
 
I'm just gonna sell my PS3 and Xbox 360 around fall and buy them again in 3-4 years for hundreds of dollars less. Super easy.
 
Why would you stream PS3 games to PS4?

Hm, good point. I had envisioned using the DualShock 4 and having the PS4 be able to provide overlay features, similar to XB1 with its HDMI in, but that's probably not such a great selling point.

Remote Vita play for all PS3 games would be nice, though, as would Sony being able to use a shrink of the PS3 silicon + h.264 encoding block for the systems they're contemplating building for Gakai streaming of PS3 games.

I've just got such a huge collection of PS3 games (60+ from PSN alone), and it'd be nice to be able to call up any of them from a single interface.
 
Why would you stream PS3 games to PS4?

So I can house the PS3 somewhere other than my living room, while having access to my PS3 content. That way I get to readily use my PS3 library on the best display in my home and my son doesn't have to worry that the PS3's presence won't have me commandeering his room from time to time.
 
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Sony is only intending to roll out Gaikai BC. It's not there from Day 1 AFAIK, and it's questionable what will come with it. It also cost Sony $lots to buy Gaikai to enable this, otherwise they likely wouldn't bother to provide BC at all. There's little incentive for MS to invent a game streaming tech just for BC.

70million+ Xbox 360 owners is not incentive? Wow!

Why would they be? MS is still selling the 360, that is their backwards compatibility strategy. If you buy into the XBone and want to play some Gears, buy a 360. Or to paraphrase an ex MS employee ' Deal with it'!

How many of them will actually play their old games? If I'm to believe the gaf crowd most of them sold their games anyway so they don't have any. The question becomes whether the cost is worth the effort? I'd just as soon they not waste engineering and silicon dollars on a feature I will never use, but how much would you be willing to pay for BC? would you give up 15% performance for it? Or pay an extra $50? Which of those strategies gets MS the most customers.

What's the cost of creating your own cloud gaming platform from scratch, or buying OnLive and kitting it out to play XB360 games? Unless providing BC is guaranteed to win back all 70 million existing customers because that's the feature they value more than any other and that alone will prevent them from considering the competition, BC isn't worth 70 million XB1 customers. It's also a feature that doesn't generate revenue, unless you are reselling people the games they already bought. It's just not a profitable venture. Sony's intentions with Gaikai extended beyond just playing BC, which is why they spent $380 million on it. I very much doubt that stream PS3 games, if they ever really happen, will generate Sony much of that money; certainly not if people are playing the games they already bought instead of rebuying them Nintendo-style.

Thanks for the follow ups guys!

Shifty you said there was "little incentive" for MS to create BC game streaming tech. My follow up was that there are 70million+ existing users that are POTENTIAL customers. Yes, they are not stopping building/selling 360 systems, but eventually they will & a good portion of those systems will eventually quit working. So MS has more incentive to keep those same customers from jumping ship to other platforms. If MS can't show to 360 owners that their investment in games(digital or otherwise) is actually worth something, then they won't garner brand loyalty & thus won't stay with them for future platforms. You said "little incentive" & I gave more than a few. I didn't say it was cheap or easy to do. I just said there was more than a "little incentive" to do it.

BTW, why can't MS game streaming tech extend beyond just BC? They original leak hinted as much. Maybe it's already part of Smartglass? Why does Sony & Gaikai get a pass & not MS?

BoardBonobo, you're right, maybe we should just "Deal with it!" LOL I've mentioned as much before. Still hard to stomach.

AlphaWolf, I agree. There would need to be some market research to determine whether it's viable feature. The cost might not be worth it I don't know. But to say there is "little incentive" is a little despondent right?

What would I give up for it? Hard to say. I think I would give up some cash as part of a monthly fee. Some might want it as part of Gold, but I think it makes more sense to sell it separately for those that want it. Unfortunately that might not be enough to finance it. So adding it to a new premier subscription tier along with a lot of other features might work. Or maybe a Pay-Per-View type system where you paid whenever you wanted access to older titles. Just a few quick ideas. I'm sure there are better ones.

The whole idea is to maximize your existing userbase to come over to the new platform. You don't do that by cutting them off completely from their old system. Gamertag, gamerscore, achievements & limited access to your friends is not a good enough incentive. It's a piss poor substitute.

With all that said, other than games & Kinect, what would you guys recommend Microsoft do differently to provide incentives for existing 360 users to transition over to XB1? I'd love to hear your thoughts other than BC is not worth it.

Tommy McClain
 
So I can house the PS3 somewhere other than my living room, while having access to my PS3 content. That way I get to readily use my PS3 library on the best display in my home and my son doesn't have to worry that the PS3's presence won't have me commandeering his room from time to time.

This. Replace "PS3" with "Xbox 360". :)

Tommy McClain
 
The only reason BC doesn't seem like a big deal because everybody tends to look at it as a feature for those wanting to have access to their old library on their new console.

There is little value in that feature. The value lies in the library. What the potential of BC if the whole pre 2012 PS3/360 library dropped into a hardware BC enable PS4/XB1's online store all priced under $5. The attachment rate for a console is usually 10 or less while a console like the PS3 and 360 has libraries that consist of 1000s of titles.

Most people don't even come close to exploring the entirety of their console library. It wasn't practical for consumers to do so because of the cost of games. But the libraries of old consoles are practically thrown away every gen. With DD becoming viable there is no reason for this has to happen anymore.

Today's $60 games can be tomorrow's 99 cent titles.
(I know the cost of bandwidth won't make that practical for a long time, just saying)

I rather keep my old hardware but then there are those that want the convenience and those who never own the previous gen version of the hardware.
 
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Thanks for the follow ups guys!

Shifty you said there was "little incentive" for MS to create BC game streaming tech. My follow up was that there are 70million+ existing users that are POTENTIAL customers. Yes, they are not stopping building/selling 360 systems, but eventually they will & a good portion of those systems will eventually quit working. So MS has more incentive to keep those same customers from jumping ship to other platforms. If MS can't show to 360 owners that their investment in games(digital or otherwise) is actually worth something, then they won't garner brand loyalty & thus won't stay with them for future platforms. You said "little incentive" & I gave more than a few. I didn't say it was cheap or easy to do. I just said there was more than a "little incentive" to do it.
Okay, by "little incentive" I meant net incentive after weighing costs against benefits. All your benefits are valid, which is always true of BC regardless of how implemented. But they all come with a cost.

BTW, why can't MS game streaming tech extend beyond just BC? They original leak hinted as much. Maybe it's already part of Smartglass? Why does Sony & Gaikai get a pass & not MS?
That's a different proposition. That's not "MS should create a streaming platform for BC" but "MS should develop a streaming platform, and then they could also use it for BC among other things" wherein the value of the platform will be found not in BC, which is worth little direct income I'm guessing, but whatever else the platform does.

AlphaWolf, I agree. There would need to be some market research to determine whether it's viable feature.
That purpose of this thread was to try and gauge how valuable BC is (or at least, hear people's opinions on the matter). IMO, the choice of MS and Sony are enough to show BC just isn't that great. Also Wii U. It's BC. It's not selling in droves. BC itself isn't reason for people to buy the next iteration. Never has been; people buy a new console for the new stuff it does!

The cost might not be worth it I don't know. But to say there is "little incentive" is a little despondent right?
I hoped PS3 would have imprved-PS2 games for BC. Instead it had nothing (for us Europeans). I've said I'd have like PS3 BC to play PS3 games in higher quality, but it's not happening. However, I understand why and I'm comfortable with it. Life moves on. The incentives, the rewards for the effort, in creating a BC platform (measured in dollars net profit for businesses) just aren't there at the moment. I expect that to change in future hardwares or complete virtualisation of the platforms.

With all that said, other than games & Kinect, what would you guys recommend Microsoft do differently to provide incentives for existing 360 users to transition over to XB1? I'd love to hear your thoughts other than BC is not worth it.
Not in this thread thanks. ;)
 
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