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Under the Hood of the Xbox 360
An anonymous reader writes "IBM DeveloperWorks is running a behind the design story for the making of the Xbox 360. The 360 has but a single chip with 165 million transistors for it's CPU " From the article: "This chip is in fact a three-way symmetric multiprocessor design. The three PowerPC cores are identical, except that they are physically reflected through the X and Y axis. Each of the CPU cores is a specialized PowerPC chip with a VMX128 extension related to (and partially compatible with) the VMX instructions in the G4 and G5 CPUs. The three CPU cores share a 1MB Level2 cache. Each processor has 32KB each of data and instruction Level1 cache. The chip's front-side bus/physical interface has a 21.6GB/second bandwidth, and runs at 5.4GHz."
I haven't been doing microelectronics since my university days (over 10 years ago) and the block named "testing/debug" intrigued me quite a bit: exactly what test/debug functions do you put on CPUs nowadays? do they contain burned in test cases? some sort of programmable logic to get access to internal CPU states? I'd definitely be interested in learning more about this.
-- the cake is a lie
What's the deal with the tiny cache? My ten year old HyperSparc has more cache than that... You'd think that when dealing with high throughput graphics applications, a larger cache would make far more of a difference than a few hundred MHz either way.
Microsoft went to ATI and IBM in order to "own" the designs for the graphics/processor chips. This way MS is able to get the parts fabbed out without having to get approval from ATI/IBM. (This is from memory of what I've read in the past). The CPU and graphics/bridge design in the XBox are owned and by Intel/Nvidia (respectively). MS had to buy the parts from them, which costs them more in the long run than being able to get their own produced.
Correct me if I'm wrong...
So from that I can conclude that the only reason to buy a PS3 is that it's a graphical upgrade over a PS2 and can support 7 controllers? Whoop-de-doo.
I'll ignore the fact that most of your points are (a) unconfirmed or (b) simply false, because I have better things to do than argue with some kid who, by the time the PS3 actually comes out in the US might have saved up enough pocket money to buy one.
Oh and you forgot the number one reason to own a PS3 - comes with a free rootkit!
---- Den ene knappen er powerknapp, den andre er Bender voice knapp "Bite My Shiny Metal Ass"
Incidentally, this means that when the XBox 3 rolls along, MS doesn't have to go through the nightmare of begging its component manufacturers for a license to emulate the 360 hardware (which seems to have been the major roadblock to Xbox emulation on the 360).
Give it a few more weeks, it will.
"Who are in control, they are not in control of anything - they don't even control themselves!" - Glen Beck
The PS2 Emotion Engine has the same design philosophy: choosing to do small memory/cache in favor for very wide bandwidth. It makes for some interesting programming juggling and kung-fu since the data comes straight from memory dumped to the graphics so nothing is cached. The results speak for themselves since the PS2 is the oldest and the most dated performance the fact that the performance is extremely dynamic and probably *still not maxed*. People are still pulling tricks that no one could predict the PS2 to do. I suspect we wouldn't have games on the PS2 like GT4 or the beautiful Shadow of the Collosius if it had been made with more cache yet small bandwidth.
Of this architecture. First of all, the chip has 3 cores, and each core can handle 2 instructions, and each instruction can get to 5 processing branches.
Also it can handle 2 threads for its vmx engine and fpu engine, this is a LOT of data crunching power...
They have setup special instruction for matrix operations...
I wonder, what would be the processing power of this chip, used for sciences data crunching?
This chip is awsome...
What could be hope for the 7 core chip for ps3, but, I think the 7core ps3 chips is rather different. At xbox 360 you have 3 general purpose power cores, and at the 7 core ps3 architecure, each core is for different tasks? Rigth? Worng?
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Unless of course you don't care about any of that stuff. I own both a PS2 and an Xbox, and the Xbox gathers dust simply because the PS2 delivers a lot more quality single-player games than the Xbox does. I had a Live subscription for a while and didn't use it that much. I guess the appeal of having 12 year olds tell me how teh ghey you are is lost on some people.
I ain't evil, I'm just good looking.
Seriously, though, these are fascinating little beasts. It looks as if the concept has its roots in the Transputer, which also relied on fast and narrow point to point external links. When I first read the blurb I guessed from the description that there were 4 cores per chip and the bad ones were disabled to get the yield up, but clearly the yield is much much better than that. However, anybody silly enough to think about overclocking will need to note that the working CPU voltage is hard coded; it looks like, to get the yield at the clock speed, each device has to be individually tuned. Which suggests that the tolerances for reliable functioning are tight. Perhaps the overall error rate is not good enough for a truly general purpose computer which needs to be able to tolerate a range of operating conditions without significant error. Which doesn't suggest a range of motherboards and retail boxed processors any time soon. Just like Apple, in fact. This reminds me of good old ECL based computers (whose CPU voltage had to be adjusted on the fly for reliable operation rather than set up once for all, but I'm sure you take the point).
It's perhaps a pity that the design teams for the Mac Mini and the XBox couldn't be locked up in a development lab with a progressively increasing caffeine level in the coffee until they create the hybrid that would really be the future of home computing. Apple's thermal management and sound level control, IBMs obvious chip development capability, and Microsoft's willingness to spend some of its cash pile would be a formidable combination. The trouble is, you'd probably end up with Apple's's ability to design chips, IBMs willingness to lose money, and Microsoft's thermal management and general aesthetics.
Pining for the fjords
Now now... this perception is a direct result of the incredible marketing engine behind the 360. The more press a particular product gets, the more negative press it will get following any sort of failure. Sure, the failure rate is 1%, lets say, but in today's world, when you shove something in peoples' faces and market the heck out of a $2-4+ hundred dollar product, those who put out the money for said product are going to be most upset if they recieve a failing unit.
I know there is nothing more annoying than getting a bad mobo or expansion card for my PC, for instance. However, ABit or ATrend hardly ever advertise, let alone to the blitz-level that MS hit for the 360, so the general public won't really care too much about my failed board. But because the 360 has the attention of the masses now, the press realizes that any negative story about the 360 is gold in their laps, and so those stories are equally as hyped.
Putting yourself out there is just that - putting yourself out there. If your product performs, you're gold. If there are problems, clean-up will be something difficult.
Excuse my speling.
Making The Bar Project
It's actually because I have friends that I don't play online games. I much rather have everyone over for gaming that meeting on line. I should clarify, it is because I have friends in the same region as me that I don't play online games.
So the big difference is that the 360 is more like current multicore PC's while the PS3 seems to lean more towards a cluster setup like openmosix.
As to wich is better? Well look at recent PS2 games. They show such graphical improvement that it might be true that PS2 still has untapped capabilties. The X-box on the other hand is pretty much at its limit. This was clear by developers complaining the PS2 was hard to develop for and the x-box was easy. Same with the next generation.
Given that the cores have the same basic design (64bit power) and Sony claims the same or even higher clockspeeds it would be easy to assume that 7+1 core > then 3 cores. I also seen larger cache sizes being claimed and even faster bus speeds. Is it all true? And even if it is will game developers succeed in tapping those resources? And even if they do, will that result in fun games?
Remember that currently the fast majority of games do not take advantage of dual core PC's even hyperthreading is rarely supported worse having it on can sometimes degrade performance. Now imagine having to write your code in such a way that it can be split across 7 processors. OR is that central core in te Cell processor capable of splitting up non- threaded applications? (Just random quesswork). After all it is supposed to be become more then the current PS3 chip it is supposed to be included in the next generation of TV's and other entertainment products.
That would be a huge advancement. The holy grail of grid computing (the cell is supposed to be like that) were you no longer have to worry about the specifics of your enviroment but can just run your code and the system will take care of it.
What I find a far more intresting proposition that with the PS3 supposedly so powerfull yet also so similar to the 360 is that it might just be possible to run 360 games on the PS3.
As for using consoles for number work. Already being done with both systems. They are so cheap yet so powerfull that all you have to do is wait for someone to break them open. Same as PC GPU's are being used for number crunching work. However GPU's is no problem wereas circumventing the PS3 or 360's protections might be in more repressive goverments (such as found in the west).
All off the above is just random speculation based on hilarious press reports. Any resemblance to the facts is unlikely.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
You don't accept them. You utilize the warranty and get it fixed.
It isn't reasonable to expect every unit to roll off the line and make it into your home flawless. Nothing would ever be make it out of the factory if that was the requirement.
It is reasonable to expect a company to stand by their product if you get one with a defect. By all accounts, that is happening; replacements arriving in 5 days, with everything handled via overnight shipping.
Justifying what I'm seeing here as "slashdot loves to bash Microsoft" IS acceptable, because the failure rates ARE less than the industry norm AND Microsoft's warranty service for problem units has been exceptional.
I doubt I should even try to put out the good games list of ps2 titles (that will also be ps3 titles when it releases, no questions asked[1]) Needless to say it puts the 360 launch list to shame.
Granted, I don't know a whole lot about what games are coming soon to the Xbox 360 for lack of time, but by the time the Playstation 3 comes out, Xbox 360 will have a lot more games by great developers and I'm going to venture a guess and say the premium system won't cost as much as the PS3 will.
Probably will, as all systems seem to launch at a high price with a mostly crap lineup. However backwards compatability out of the box means that I won't have to switch any plugs around to play games I bought a few months before the system released.
That was my point, was that waiting for a PS3 was stupid. You get less (no unified online service, which is a BIG, BIG portion of why you should get an Xbox 360 over PS3, no titles from Rare or Bungie)
I can get better online service from my pc, and it is free. Rare and Bungie have yet to do anything terribly impressive that is not also available on pc. Name a few games aside from an fps where online service really matters? It just is not the big deal you think it is, unless you are into fps's, where (imo) keyboard+mouse is a better setup anyways.
and get some things that are somewhat unpleasant (blu-ray: Who really wants a disc format that can brick your system of the manufacturer tells it to? How long before it's cracked and a virus is written?
So you think someone will release a program that actually does brick a system?[2] As for "viruses being written" there is the slight problem that you have to PUT THE FREAKIN DISK IN THE DRIVE. Unless you have ninjas slipping into your house while you sleep to brick your ps3 this is a non-issue, and if that is happening you have bigger things to worry about than your consoles.
Who really would be angry about getting up every few hours to change a disc? Big deal. None of us had problems with it in the PSX days.)
I would. People had no problems with traveling for days on end when hitching up to a horse was the only way to go, but society moves past these sort of things. Multiple disks means I have to keep track of more than on disk, and run the risk of renting a game that I can play for two days THEN find out some idiot scratched one of the other disks. It is hard enough to get my roommates to put a single disk back in the case when all the necessary parts are sitting right there, several of them just compounds the problem.
[1] Unlike the xbox, where support for the previous system depends on them figuring out a way to make that specific title work. [2] Not to say that I agree with the concept either, but the backlash against it being used is going to be enough of an inhibitor to keep that from happening.
Slashdot: Where anecdotes and generalizations can be freely substituted for facts, logic, or intelligence
Could it be used to make sure that only code signed by Microsoft can run in a virtual machine?
I know for a fact the 360 is using Virtual PC for XBOX emulation, but I haven't heard that there is any hardware-level virtualiation for the 360. It can't be built into the CPU core(s) as they're fairly well understood so that means some sort of software level virtualization and it's difficult to imagine that would be worth the performance hit. And it seems to me a monumental task to make a emulator that would perform well emulating a cutting-edge GPU like the one in the 360. And I'm really dubious of the notion that this would provide any additional content protection. You could easily implement some sort of key-signing in the OS, without having to waste valuable hardware space.
But if you're saying that the "Virtual XBOX" emulator for the 360 probably won't run unsigned code, then yeah, you're probably right.
But will it have a TV output? And will your Free operating system's X server be able to draw to the TV output? Not everybody likes to crowd four people around a 17" monitor. And will it come with a gamepad for playing games other than FPS and RTS?
Linux-compatible TV-tuner card, $20. USB gamepad, $20. (Or if I wanted to I'm sure I could buy the new Microsoft gamepad, $40. I bet it's Linux-compatible or soon will be.)
And it's stil an open question as to whether or not any free OS's will be able to use the TV output of the 360.
Uniquely? Compare to the Dreamcast, which can boot unsigned code from CD-R.
What I meant that it was a "uniquely capable hacking platform", in that while it wasn't as easy to hack as some other systems you could do a lot more with it than with other consoles due to it's familiar architecture. The capabilites of the DC were pretty limited in comparison, especially if you didn't have the broadband adapter.