Phil M Perry wrote:
>> So Ubuntu's installed, but I don't understand /why/ it worked.  How 
>> would the copy I burned be any different from the one that Ubuntu 
>> pressed?
>>     
> Well, that's strange. All I can guess is that it's a marginal original 
> copy (the pressed disc) or a marginal drive.
AFAIK the drives on my own and my parents' computers have no problems.  
Also, neither drive had any problem /copying/ the pressed CD, or running 
its own verification routine.  I'd guess a marginal disc.

BTW I'd tried installing the pressed CD a second time, with 'noapic' and 
a batch of other parameters, and it failed at a different, slightly 
later spot.
> Normally, a /pressed/ (stamped) disc is
> read quite reliably. CD-Rs and CD-RWs are usually less reliable (do you
> know for sure whether the Ubuntu distribution was on a CD-ROM (pressed)
> or CD-R(W) (burned)?
I didn't think to check that.  I suppose it was a CD-ROM, since the 
label side had the red Ubuntu label on it.  It's at my parents' house, 
and all I have are my own copies of it.
> The higher the speed, the thinner the dye layer, and
> the faster the write (but less reliable the read).
The copy I made on my parents' system was done at 40x or 48x, and the 
copy worked just fine.
> Compared to the Windows
> settings, Ubuntu must be a tad more aggressive in its read settings, and
> failing on a marginal disc that Windows could read.
I made copies of the pressed CD for myself on my own system using k3b 
under Mandriva without any problems.  I didn't try to copy the pressed 
disc under an Ubuntu installation.
> I wonder if there's any
> way to set Ubuntu's read to a bit slower without a recompile? A way that
> would work on a boot-up install disc? *This is bound to be a problem for
> a lot of Ubuntu customers, particularly if the discs were cheaply
> pressed, and many of them are going to give up in disgust and stick
> with Windows!*
>   
Maybe everything was usable on the equipment at Ubuntu HQ and the 
pressing plant, so they assumed it would be OK on all systems?

I don't think this has anything to do with it, but I'd also downloaded 
the ISO image of Ubuntu 8.04.1 from Ubuntu's web site, and compared it 
with an ISO made from the pressed disc I had, and they were NOT 
identical.  IIRC the one made from the pressed disc was a little longer, 
so I went with that and erased the downloaded ISO.

I should search online and see if anyone else had problems like this.  
Thanks, Phil, and everyone, for sharing your expertise on this!

Adam

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