[OT] But important to me. Appropiate Mailing Lists ??

James Wilkinson fedora at westexe.demon.co.uk
Wed Apr 19 12:15:23 UTC 2006


Markku Kolkka wrote:
> No, all components are powered on at the same time. (large servers
> may use power sequencing to limit the maximum start-up current draw,
> but that's not relevant to BIOS start-up).
> See: http://www.pcguide.com/ref/mbsys/bios/boot.htm

William Case wrote:
> I'll double check, of course, but I seem to remember reading that one of
> the first functions of main BIOS is to wake up/start the other BIOSes.
> I have been to the pcguide bios site but I'll read it again.

*Powering up* and *starting* are two separate things.

BIOSes used to be on ROMs -- read only *memory*. These days they're on
erasable programmable ROMs, but that's a minor detail.

There's a bit of handwaving going on -- BIOS is used to refer to the
chip itself, and to the logical data and programs that are stored on the
chip. The chip does nothing by itself -- it just makes the data
available to the processor.

When a processor turns on, it is set to read a certain memory address
and run the instructions stored there -- and the motherboard is designed
so that that memory address is part of the BIOS. From there, the BIOS
sets itself up, and eventually gets around to reading the other system
BIOSes.

This happens at multiple megahurtz, so it doesn't take that long in
"wall time" for the system to get far enough to wake up the video BIOS.

> Honestly, I don't mind doing the work, but sometimes the concept gets
> past me, the search criteria are wrong or mis-posed or I would just like
> to talk over some of the issues that have come up.  As you can see, they
> are not all Fedora related although most of them are Linux questions.
> (The BIOS questions above are an exception.)

This list is "for users of Fedora distributions": I'd call generic Unix
or Linux questions on-topic here.

James.

-- 
E-mail address: james | "We've just been contacted by the Lady of the Lake."
@westexe.demon.co.uk  | "Really? What does she want?"
                      | "A really big towel."
                      |     -- http://www.mopsy.com/d/19981122.html




More information about the fedora-list mailing list