Re: PCI lifetime

[Daev Roehr <daevr@atc.creative.com>]

Gerhart
> In several discussions with hard- and softwaremanufacturers I heard the opinion that the PCI bus will not survive the next two years in end user PCs. The only bus system that will survive is the USB and Firewire serial bus. Is there any more information available other than mere opinion? Does a road map exist for desktop PC designs?

This has been floating around for years, much like internet "urban
legends" do. I refer to this as the great "No slot scare of 96". :-)

A couple of points to consider: 

1) It takes a long time to adopt a new bus architecture. Motherboards
and cards need new chip designs, OS's need architectural and driver
changes, (not to mention new drivers!) there's certification and
reliability issues, and so on, ad nauseum. Observe the 1980's ISA slot
is still available in a lot of PCI machines today, although the PCI 1.0
spec was published in 1992.
2) PCI as a *technology* will be around a long time, even if full size
PCI card slots eventually go away. PCI is the foundation for the follow
on to PCMCIA (Cardbus, widely adopted), it's used as a system board
interconnect for sound and network chips, it has already has several
enhancements for bandwidth (PCI-66, AGP, PCI-X), and it has several
newer form factors (modem/audio/net risers and Compact PCI for example).
3) Finally, PCI is an internal bus, whereas USB and 1394 are external
busses. This is a key point of differentiation: Although the final
customer wants expansion capabilities, they don't want to open their PC
to do it. 

So another way to look at this comment is that PCI slots may be moving
more towards being a vendor "build to suit" configuration option,
whereas the final customer prefers to not open the box. Two different
problem sets.


Richard,
> Hm, what about busses like HyperTransport, RapidIO, 3GIO, Infiniband. I thought these were meant as inter IC buses unlike USB and 1394. Would be nice if someone could shed a light on this.

Based on the adoption rate of PCI-X, I wouldn't hold my breath. The
final PCI-X spec was published in late 99, and we're just now starting
to see high end IA-64 systems with PCI-X on them. Although these other
new buses will certainly find markets in the various spaces (mostly
servers), I doubt whether they will have significant deployment in the
broad customer space in the next 5 years. PCI for an internal bus and
USB/1394 for external busses are well entrenched, cheap, and frankly
good enough for most people. For internal busses and connections, the
changing Northbridge/Southbridge market conditions make a new generic IC
interconnect standard unlikely, IMHO.

Anyone with contrary opinions, feel free to chime in. Keeps thing
lively! :-)


-- 
regards,
_daev

 * * * * * * * * * * * * * * * * * * * * *
   Creative Advanced Technology Center
  Daev Roehr, Liaison Engineer ala mode
 daevr@atc.creative.com - 831.440.2832
"Stanley looked quite bored and somewhat 
 detached, but then penguins often do."
     Edward Bulwar Lytton prize