April 27, 2004 - Chinese website GZeasy revealed an alleged blueprint of Xbox 2, labeled Xenon System Block Diagram, earlier today. The diagram is believed to be the basic concept for the next Xbox, which is either codenamed Xenon or will, in fact, be called Xenon. Though some aspects of Xenon may change slightly over the next year, the diagram is believed to be a close representation of Xbox 2.
Michael Dougherty, head of Xbox Advanced Technology Group, has his name attached to the document, though that doesn't make it any more legitimate. However, the diagram was confirmed as the real deal by a developer close to Microsoft. "We were very surprised to see that leaked," a source, who wished to remain anonymous, told us this morning. "I'm sure Microsoft is freaking out because this is the same stuff [developers] have now."
Other sources have claimed that the document is not real and claim it is a fake. The main point of contention is that the document doesn't state what type of RAM will be used, something that's quite important for development considerations. A Microsoft representative stated, "Microsoft does not comment on rumors or speculation" -- but Microsoft's legal department requested that IGN does not reprint the schematic on its websites. While most signs suggest that the document is authentic and of high importance, note that it is also possible the leaked blueprint is an older document never meant for the public eye and that the current architecture of Xbox 2 is quite different.
What does the fancy diagram that Microsoft doesn't want you to see mean? Though it doesn't offer cold hard facts as to what "Xenon" will be capable of in terms of full processing power, one thing is clear -- this baby will be quite powerful. Xenon is divided into essentially two sections. The section on the left of the machine, the South Bridge, is standard stuff. That's where your DVD, Ethernet port, and potential hard disk go. Note that the hard disk is not confirmed, even in this diagram, but if it is to be used, expect 20-80 GBs capacity.
The more interesting parts of the diagram are on the right. Think of the North Bridge as your highway of importance and everything attached to it -- graphics, sound, AI -- are all of the information needed to run a game. All of that needs to get pulled onto the highway and brought to the South Bridge. There are wide open lanes to the North Bridge from every area, incredibly wide, with 10.8-33.2 GBs per second bandwidth able to be transferred along the pipeline. That is unbelievably fast.
Of course, a quick pipeline means nothing if there isn't processing power behind it all. Taking a bike onto an empty freeway still isn't going to get you anywhere quickly. The first and most important item to note is the upper box on the diagram. There are three 3.5+GHz CPU chips. Each of these will likely be used to handle different aspects of Xenon processing. Each also has its own separate cache and a global cache. All of this means that while Xenon will likely use grid processing or some form of collaborative "cell" processing (IBM does something similar with "Butterfly" very well), as opposed to the more common dual-processing. Each CPU can then work independently to govern different game needs, but because of the shared cache, and because each is a Virtual Processing Unit, programmers will see it as, essentially, one unit. They won't have to meticulously program specific functions to each processor, but instead can rely on Xenon to choose where to distribute everything. None of that Sega Saturn insanity here.
Below the North Bridge is the all-important graphics chip. The 500MHz clocked core chip has 10 Megs of dedicated EDRAM, which will likely be used for more specific special effects. While that doesn't sound like much, Microsoft's current console has no graphics-dedicated RAM. Those 10MBs will keep a majority of the 256 MBs of main RAM free for other applications. This chip, presumably still of ATI make and specially created for Xenon, looks to be beyond the best graphics available on PC now or in the foreseeable future, but should be comparable to those high-end cards by the time Xenon is release in 2005 (unless it's delayed).
To the right of the North Bridge is the Main Memory, which at 256MB may seem small compared to your personal computer, but remember that Xbox only has 64MBs and does not have any memory specifically dedicated to graphics or special effects. All of that memory can be pumped across the system bus at 22.4 GBs per second. More bandwidth across the board means less choke points, which translates to higher performance.
If this diagram is real, reasonably up-to-date, and if this is the blueprint for Xbox 2, then gamers are in for a whale of a machine, one far more powerful than any current generation console. We'll have more on this story as it develops.
-- Hilary Goldstein & Ivan Sulic
just like bear meat
I don't like it.
"There are three 3.5+GHz CPU chips"
Sounds nice!!!!! Can't wait, I just hope you can play the old xbox games on it.
Alleged Xbox 2 specification sheet debunked by experts
Rob Fahey 15:57 27/04/2004
"Leaked" diagram is a fake or, at best, an out of date internal document
A diagram purporting to be a leaked Microsoft document describing the specification of the Xbox 2 has surfaced on a Chinese bulletin board - but sources close to the console's development say that it is probably a fake.
The block diagram, which appeared on Chinese website GZeasy.com, shows a system architecture which had three 3.5Ghz CPU units, 256Mb of main memory, and a 500Mhz graphics chip with 10Mb of on-board memory.
The schematic also shows the system featuring two memory unit ports, with basic memory unit size being 64Mb, a 100Mbit LAN port and a hard drive - although it notes that it's not been decided whether to build in the drive as yet.
However, a number of sources who are familiar with Microsoft's console development say that the diagram is not an accurate reflection of the information they've received from the company about Xbox 2 - and could easily have been put together by someone with basic hardware knowledge from publicly available information about the forthcoming system.
"It's not impossible that it's a Microsoft document," one expert told us this afternoon. "But some of the figures seem very suspect, and the information included on the diagram looks to me like it reflects the available information about Xbox 2 rather than being a sensible set of information to put on a document for developers."
He voiced particular concerns over the fact that while the document notes "256+ Mb" of main RAM, it doesn't state what kind of RAM will be used - a vital technical point - and also noted that the CPU diagram doesn't mention that the CPUs used will be dual-core (effectively making Xbox 2 into a six processor unit), another important factor.
"There's a lot of detail here about stuff you could just guess or which we already know from public announcements, like some performance information about ATI's graphics chips. And then there's some really surprising missing detail, like the twin-core architecture and a few other really crucial things which Microsoft has already talked to developers about but are missing from this diagram. I'd have to guess it was a fake," he concluded.
Other developers familiar with the Xbox 2 architecture also voiced misgivings about the diagrams, with one pointing in particular at the information about the processor cache on the document as being inaccurate. "We've seen stuff about the cache on those CPUs from Microsoft, and this isn't it," he said. "If this isn't a fake, the only thing I can think of is that it's an old internal document that was a work-in-progress and never meant to be seen outside Microsoft."
Phew. That thing would have cost a friggin fortune. 4 processors!