[G4] ATA BUS QUESTION

[Harry Freeman]

Greetings ( + )!( + )

Thanks for your interest, however there is nothing out of the norm in 
my "1999 G4 350 MHz" platform that didn't come from Apple. So let's 
assume that the drives are set for cable select, connected via the 
ribbon cable that was supplied with the platform.

The one thing that I may have missed passing along was that the system 
had ran fine for seven years, starting with OS 8.x then to OS 9.x and 
then to OS X 10.3

The only things that were changed was that I added two (2) 120 Gb IDE 
drives and removed the original 20 Gb drive. I also expanded the RAM to 
1.75 Gb and up-graded the processor to a PowerLogic 1.2 GHz unit from 
OWC.

When I installed the 120 Gb drives I have partitioned the disk into 
four (4) partitions because of the way OS 8/9 assigned sectors on large 
disk drives. If your stored data was not large then you could 
conceivably have a lot wasted storage space, i.e. unused because the 
file wouldn't use all of the space that had been allocated for that 
sector.

On these four partitions I had OS 9 on two and OS X on two, and could 
select any of the four partitions as the start-up partition and never 
had any problems. I also had OS 9 and OS X on the other 120 Gb drive 
and could select either one of those as the boot drive, so there wasn't 
anything special going on under the hood.

So after installing OS X I have been wanting to remove the partitions 
because UNIX handles data in a different way than it was handled in OS 
8/9, however during the formatting of the 120 Gb disk and then trying 
to restore the data from the four (4) partitions something went wrong 
and when I tried to restart for the other disk the internal working of 
the platform wouldn't let me choose the second disk.

The first computer that I worked on was the "Ground Guidance Radar 
Computer" for the SM68A Titan I ICBM in 1962, which consisted of an 
Analog and a Digital computer and I have worked on many various other 
computers throughout my career, so I'm thoroughly familiar with most of 
their intricacies. My first UNIX system was a PDP-20 or was it a PDP-40 
it's been a long time, my next UNIX was a Sun workstation. I worked for 
a company that provided the Sun work station as network control and I 
provided tier 3 technical support.

As I tried to point out in my original posting, unless Apple says that 
you should have the main boot disk in a specific location, I think that 
it doesn't matter very much.

A second point is that I do believe that Apple does recommends that the 
main boot disk is the second disk on the ribbon cable if you are using 
the original IDE controller card.
----------------------------------------------------

On Apr 29, 2007, at 5:39 PM, Ronald Steinke wrote:

> On 28 Apr, 2007, at 4:50 PM, Harry Freeman wrote:
>
>> So my bottom line is, yes it might make a difference which order the 
>> drives are installed, but you can usually overcome any problems that 
>> might arise.
>
> Perhaps you are correct in this statement, but - you never did tell us 
> how you had the drives identified and connected to the IDE ribbon.
>
> Were they on the same ribbon? Were they identified as Master and 
> Slave? Was one of them set to Cable Select? Was your IDE ribbon a 40 
> wire instead of a 80 wire type? Does your IDE ribbon have one blue 
> connector, one gray, and one black?
>
> These factors can definitely have an effect on the startup procedure 
> if one of the drive configurations is not compatible with the rest of 
> your system.
>
> Working with a computer recycling organization that primarily 
> processes PCs, I get to see many problems from across the room. Some 
> of the solutions I have seen actually depend on the direction that the 
> ribbon is installed, ie: blue connector in MoBo, not in hard drive.
>
> No, I do not work on the PCs, only on Macs, but some of my experience 
> and knowledge is based on what happens across the room. Yes, we 
> usually do find a way to make the darned PCs work properly. If 
> everything that is tried fails to correct a problem, we can always 
> scrap the thing out and reuse some of the parts at least.
> _______________________________________________


Cheers, /\*_*/\

Harry (*^_^*)
* If pro is the opposite of con, then what is the opposite of progress? 
Congress!
Men's restroom House of Representatives,
Washington, DC