melgross: The PPC is now officially a dead end street.
My take as well, as the problem isn't the CPU, it's the chipset and all the other logic that makes for a "real" computer.
SamuraiCrow: Amigas have always run on embedded controller versions of the 680x0 series so why would embedded PowerPC models be any different?
PowerPC isn't widely applauded for compatibility. By comparrison, the infamous 68000 didn't change very much over the years. Complex bus logic is also built into CPUs these days, and external logic must be matched accordingly. It's expensive, especially without good chipset support.
SamuraiCrow: It seems, then, that Intel is getting relegated to the desktop in a market where embedded systems and consoles are taking over. Which one's the dead end?
Coding practices are very different. Desktop-style programming demands heavy abstraction. Embedded systems and consoles encourage the use of special instructions and features that are not widely available, even on other devices using the same family of CPUs.
There are good reasons why the CPUs are developed the way that they are for each market, and the architectural directions they take are based on market demands. It's not easy or practical to swap processors between markets, especially if the development tools are designed for a particular purpose. Availability of tools is a major issue, since that's how you make things forwards compatible, not just backwards compatible. I seem to recall that forwards compatibility isn't a major issue in the console/embedded market. If it is, developers usually take the easy way out and use Java. *shudder*
melgross: Despite what you may have read, the Cell is only marginally a PPC chip. While the Xenon is closer to the older G4 line, with improvements, and deletions, the Cell is vastly different. It requires a very different programming model.
I've heard the PPE core in the Cell is more or less used as a preprocessor to keep the SPEs fed.
SamuraiCrow: Speaking of not changing, the Playstation 3 will probably not change for the life of the product for compatability reasons. The Commodore 64 also followed that same pattern. The C64 was the best selling single-model computer in history.
The C64 also didn't have a real OS, people had to give up on their software when moving to the Amiga (or whatever), and there were a lot more games available than apps. Even commercial programs required some POKEing every now and then. What a pain.
With all this open-sourcing going on, and the fact that the Amiga pretty much
started the public domain and shareware scene, it shocks me that many Amigans still want to shackle themselves to closed hardware.
SamuraiCrow: If anything, that gives IBM the incentive to be more creative as the Cell processor and the Kilocore processor indicate. IBM is making great strides since Apple forced them out of their comfort zone.
They can afford to be more daring as backwards compatibility isn't a major priority, and if it is, IBM is being commisioned to do custom design for a specific platform that wouldn't be available to other companies without a hefty price tag. If you buy a Cell processor, you're paying Sony, not IBM, and you have to pay IBM indirectly for the work they did on the processor. More middlemen, plus, you still have to have a custom motherboard made. Specs look good on paper, but real-world practicality is lacking.
All of this to do... what? Web browsing? E-mail? Running 68K emulators?
Why bother with so much custom hardware if it will take forever to make OS tools to use it correctly? What about the budgets required to make those tools and port them every time the architecture changes? It doesn't make sense to hype a specific processor type unless you intend to hard-code it, and that is suicide for any real OS. The whole point of an OS is so programmers don't have to worry about the hardware. How abstract the OS needs to be depends on the usage, and desktop computers are really designed to do just about anything.
Release an OS first, get it in the hands of developers, get the basics out of the way, and then you can worry about cutting-edge hardware concepts.