Inside the Xbox 2 - Part 2
By: Cesar
Dec. 9th, 2003 07:18 am
Contrary to other sites, we usually don’t report every single rumor that we hear. It is easy to post rumors about fake stories like Halo 1.5 arriving on Nov. 15 or Perfect Dark Zero being shown at X03 than going to the source and finding out if there is any legitimacy to the stories.
When believable stories land in our laps, however, we take things seriously and dig deep to bring you the goods. You might remember a little story that we posted regarding Microsoft teaming up with IBM to manufacture the Xbox 2 CPU. It was a world exclusive and of course, with long-time rivals being the protagonists of the rumor, nobody believed our story. Low and behold the story became official on November 3rd with the announcement of a semiconductor technology agreement between Microsoft and IBM.
So far, Microsoft has announced three partners for its Xbox 2. First ATI, as its prime graphics supplier; then IBM as its semiconductor processor technology provider, and finally SiS as the chipset contractor. What do these companies have in common? A lot. And suspiciously, all roads lead to AMD.
The ATI/AMD64 Connection
ATI replacing nVIDIA as the graphic chip provider for the Xbox successor was a no brainier. The Ontario-based graphic chips maker has proven its R3XX VPU is far superior to nVIDIA’s offer, the GeForce FX family of GPUs (aka NV3X), especially under DirectX 9 Shader tests. The future of graphics is all about Pixel and Vertex Shader programs.
The interesting part of this connection is not the graphic processor that ATI will provide for the Xbox 2 (check our early preview) but the chances ATI might also design the motherboard chipset. It is worth explaining that nowadays the chipset (a set of integrated circuits to support the processor) basically consists of a couple of chips, the North Bridge and the South Bridge; found in the current Xbox in the form of the XGPU and the MCPX chips respectively, both provided by nVIDIA.
Last month, at its Reseller Seminar in Korea, Advanced Micro Devices revealed some future ATI chipsets for the AMD 64-bit platform. It’s particularly interesting that the RS480 (a North Bridge) features an integrated DirectX 9 graphics core using UMA (Unified Memory Architecture); a technology already used in Xbox for its 64 MB of RAM. Accompanying the RS480 is the South Bridge providing I/O capabilities; the IXP400. Both core-logic products will go into mass production in Q2 2004.
The IBM/AMD64 Connection
Although IBM is instantly associated to the PowerPC architecture, several sources within the videogame and chips industries have told us that the Xbox 2 CPU won’t be a PowerPC. I repeat: it WON’T BE a PowerPC processor. And we’re starting to believe them.
So far, no one has dared to confirm the Xbox 2 CPU will be a PowerPC processor. Everyone speculates about its architecture but nobody has been able to confirm it.
Switching to a PowerPC CPU, and therefore abandoning the x86 architecture, would make pieces of one of the flagship advantages to the original Xbox: ease of development. On top of that, you have to consider switching from x86 to PowerPC would make backward compatibility not a viable feature, unless they use a state-of-the-art emulation technology such as VirtualPC from Connectix, now a Microsoft company.
But where’s the IBM/AMD64 connection? Everywhere. Last January, Advanced Micro Devices and IBM said they were co-developing microprocessing technologies for use in future chips. Specifically, their joint venture is intended for develop semiconductor manufacturing technologies for 65-nm and 45-nm chips (a nanometer is one-billionth of a meter). Current microprocessors are built using a 130-nm process implemented on 12-inch (300mm) silicon wafers. Both Intel and AMD plan to switch to a 90-nanometer manufacturing process early next year.
Furthermore, several publications have reported that AMD engineers are being re-located from AMD’s Sunnyvale offices to AMD-IBM joint venture R&D centre in IBM's East Fishkill facility.
The Microsoft/AMD64 Connection
AMD doesn’t have the financial power to prevail against Intel. This quarter would be the first time in nearly three years AMD has made money quarter to quarter. Now it’s embarking on building their 65-nm Fab 36, which will cost $2.4 billion to construct. So AMD needs one thing in the coming years: cash. Who has lot of cash? Microsoft. A few months ago the Redmond-based company was considering paying a special dividend of $10 billion to slim down its cash reserves of more than $46 billion!
It is also worth mentioning that a 64-bit version of Longhorn, the next version of Windows, has been already sent to testers, even before the 64-bit version of Windows XP for AMD64 hit the streets. Depending on the release date of Xbox 2, the Xbox successor might use several (if not all) of the new technologies Microsoft is developing for Longhorn, including DirectX 10 and Palladium security technology.
The SiS/AMD64 Connection
Just one month ago, Microsoft announced that SiS Corp. will be developing “advanced media Input/Output technologies†for the Xbox 2.
Guess who has the best chipset for the Athlon 64 these days? nVIDIA with the nForce3 150? Nope. Via with its K8T800? Wrong again. The correct answer is Silicon Integrated Systems with its SiS 755/SiS 964 chipset. It won the Editor's Choice as the best Athlon64 chipset at Anandtech.
Part of SiS’s lead in performance is thanks to its proprietary MuTIOL 1GB/s Bandwidth bus, which avoids a slower North/South Bridge bus; a common problem found in competitors chipsets. SiS’s offer is the only one that connects the processor at the highest HyperTransport (an AMD spec to interconnect devices) speed while offering an equally speedy bus to connect both the North Bridge and the South Bridges.
Although the most likely scenario is that SiS is building an entire chipset for Xbox 2, it is possible that Microsoft is only licensing their MuTIOL technology. Only time will tell.
It is worth mentioning that the current Athlon64 and Opteron/Athlon64FX processors have a built-in DDR memory controller, resulting in motherboards that have a non-standard North Bridge -- the part of motherboard chipset that holds the memory controller. This implementation also implies an improved memory performance.
Conclusion
To sum things up, it is possible that the Xbox 2 might use an AMD64 processor (Athlon 64FX or the upcoming K9); probably a modified version, highly optimized for gaming purposes (ala Intel PIV Extreme Edition), that will be built by IBM using the most advanced manufacturing process available at the time the Xbox 2 ships; probably a 90-nanometer manufacturing process or, a 65-nm one, if the Xbox 2 arrives late 2005/early 2006.
The chipset could be designed by ATI, using some licensed technologies from SiS. That would have ATI not only designing the graphic processor but also the chipset; just exactly as nVIDIA does nowadays by providing their NV2X GPU and nForce chipset for the existing Xbox.
So there you have it. This is our small conspiracy theory. It is pure speculation but based on rumors, inside info, and technology facts.
Today, our friends from The Inquirer have a couple of interesting stories regarding Microsoft, IBM, AMD and Xbox 2, which help to support our theories. Be sure to check out their stories, available on their website at this URL.
TeamXbox
So an AMD CPU? If I remember correctly, Panjev speculated this might be the case when the IBM news broke a while back.
I don't think any x86-64 chips could as "the lastest in IBM's family of state-of-the-art processors."
Why do you say that? I admit - assuming CELL does end up in PS3 - that each APU being a PPC core is quite ambitious. But there is still very little solid information about PS3. For e.g, a "CELL CPU" may be implemented as an "abstracted"(well, more or less) "processor farm" in the system, with a seperate MIPS/PPC CPU(s) farming instructions to the CELL, controlling main program flow, etc.