[rescue] OT: FeeCee rescue

Jonathan C. Patschke jp at celestrion.net
Tue Sep 30 16:05:52 CDT 2003

On Tue, 30 Sep 2003, Derek Andersen wrote:

> Just out of curiosity, why is a G3 (presumably running OS X)
> 'acceptable' while (say) an x86 laptop running Linux (or Solaris x86, or
> whatever) not? Is it just the CPU?

Firmware, G3:  OpenFirmware.  Complete diagnostics and FORTH interpreter
in ROM.  Can boot from any device, even the terminal if you're feeling
adventurous.  Can boot from devices not invented when the machine was
created, so long as it can talk to OpenFirmware.  Oh, and if those
peripheral can talk to OpenFirmware, you get diagnostics on that, too.
Need to patch the first-stage loader so that you can play around with
an OS of your own?  OpenFirmware can do that, too.

Firmware, PC:  BIOS.  Can count memory on fingers and toes and tell you
whether or not your IDE drives are plugged in or not.  Beyond that?
"Keyboard not found.  Press F1 to Continue."  Programmability is limited
to plugging cards into the back of the machine and loading user-space
ROMS via chicken entrails.

CPU, G3:  It's a PowerPC derivative.  While not as ballsy as a beefy IBM
604e, it's a lot nicer than the 604e that Apple put in their machines.
No shortage of registers, load-store operation, talks little endian and
big endian and possibly VAX endian.  I think at least one variant of the
family can do BCD arithmetic.  All that, and it takes little power and
puts out little heat, too!

CPU, PC:  x86.  20 year-old CPU technology stretched thin to barely
limp by in the 21st century.  The MIPS/watt is starting to approach a
mediocre VAX.  Registers are priceless, and you can reference at least
one (sometimes two) memory addresses in a single instruction so
instruction fetching can ruin your whole pipeline something awful if you
confuse the prefetch units.  This wouldn't be a bad thing, aside from
the fact that almost -all- of x86's speed comes from deep pipes.

Peripherals, G3:  USB and Firewire.  Two buses that were designed for
expansion.  Yeah, there's IrDA, too, but no one uses it.  Want to add
another hard drive?  No problem, there's the firewire.  Want cameras,
mice, keyboards, and other goofy stuff?  There's the USB.

Peripherals, PC:  USB, PS/2, RS-232, Parallel.  Eww, eww, eww!  Look at
all those legacy high-voltage buses.  And only one of them is designed
for using more than one device at a time.  If you get more than 1 USB
port, you're a lucky dog.  Firewire just ain't there on PC laptops yet.

Expansion, G3: One PCMCIA slot.  Okay, the PC wins here.

Expansion, PC: Two PCMCIA slots and sometimes a dock.

Software, G3: Linux, Mac OS Classic, Mac OS X, BSD, whatever.  Native
32-bit from end to end, full vendor support for pretty-much everything
thanks to OpenFirmware.

Software, PC: Windows, Linux, DOS, *BSD, Solaris.  More choice, less
quality.  Vendor support is spotty under anything other than 'doze
because God only knows what sort of things you might plug into your PC
with all those device manufacturers following their own drumbeat.  So
long as it's "Designed for Windows XP", it's okay, right?

In short, it's an entirely different mentality.  You can take all the
components out of a PC (arguably omitting the CPU or at least replacing
it with a Xeon) and make a workstation out of it, so long as you dump
the BIOS, leave back-asswards compatibility behind you, get off that IRQ
brain damage, and modernize the expansion buses.  Theri's nothing about
the x86 (aside from its abhorrent shortage of general-purpose registers)
that makes it worthless in a workstation.

What Apple (and Sun and SGI and IBM) have going for them is that they
sell you the total package.  The OS, the computer, and pretty-much
everything you plug into it was either designed by the same company,
designed under the supervision of the same company, or designed to a
modern operability standard not dictated by the OS, but dictated by the
people who designed the computing platform.

They sell you an experience.  PC manufacturers sell you a box of parts,
and, if it breaks, you get to keep both halves.

Jonathan Patschke   )  "Gamer weenies...are the sludge at the bottom
Elgin, TX          (    of the user swamp."           --Gary Nichols

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