fresh install ---blooming DVD drive not recognized AGAIN

Basil Chupin blchupin at
Mon Jan 16 05:03:55 UTC 2012

On 16/01/12 15:35, Basil Chupin wrote:
> On 16/01/12 15:09, Basil Chupin wrote:
>> On 16/01/12 14:41, Ric Moore wrote:
>>> On 01/15/2012 08:17 PM, Basil Chupin wrote:
>>>> Yesterday, after several frustrating hours where I could not get my
>>>> wife's computer to work properly (I had to move the system into a new
>>>> box - don't ask :-) ), I realised that one should prepare a check list
>>>> of what to do when tackling a damn computer's innards and tick them 
>>>> off
>>>> as the work progresses :-( .
>>> I always mean to do that, but I get into "Master of the Universe" 
>>> mode, with the skin of my scalp pulsing and bulging from all the 
>>> brains packed under there, and think I'll remember it all. <sighs> I 
>>> know, someone just shoot me.
>>>> I couldn't get the darn thing to work properly because......I had
>>>> forgotten to check that the jumpers on the HDs and the CDROM and DVD
>>>> burner were correctly set :-( .
>>>> So, are your jumpers all set correctly?
>>> But of course. <smirks> I have one harddrive and one CD/DVD r/w. 
>>> Both are set to "master", as each is on it's own cable and both are 
>>> IDE.
>> OK, both on separate cables and both set to Master. Positive?
>>>> means that rather than use the 80-wire cable you regressed to the old
>>>> 40-wire cable - which is why you are getting the message that your 
>>>> UDMA
>>>> is now only 33 "due to 40-wire cable". S
>>> Secondly, you state above that you use a "newer fat one" IDE cable. 
>>> This
>>> Nah, I should have been clearer... I used a NEWER "fatter" IDE 
>>> ribbon cable to the DVD drive. It's still the old IDE flat ribbon 
>>> style though. It LOOKS nicer, and a little more heavy duty, so it 
>>> ought to work better? Heh, the optimistic side of me shows.
>> So this newer cable IS 80-wire cable, right?
>> In which case the kernel is not recognising the full UDMA of the 
>> drive because it is giving you the message that the UDMA is 
>> restricted to 33 because of the "40-wire cable". To get the full UDMA 
>> for your drive you then need to apply the fiddle I gave in my 
>> previous response.
> I shouldn't have skimmed over your reply and should have written above 
> that the fix you ought to be using is  'libata.force=2:80c' because 
> your DVD R/W is on the second channel. But if both the HD and the DVD 
> are showing the wrong UDMA then use 'libata=1:80c,2:80c'  (which is 
> what I have to use because I have HD and DVD R/W on channel #1 and HD 
> and DVD R/W on channel #2 and without the fix dmesg shows that all are 
> configured to UDMA33 because of the "40-wire cable" trick.)
Awwwww, HECK! :-( . I'll get this right any minute now.....

I just looked at my notes re this libata thingie, and there are 2 things 
I need to add:

1. my notes state to use 'force=x:80c' [no 'libata' before the 'force'] 
"if not statically in the kernel" - whatever "if not statically in the 
kernel" means - where "x" is the channel number; and

2. probably much more important, is to run 'sudo grub-update' after 
inserting the 'libata.force...' statement in the menu.lst .

I think I've got it all now :-) .


PS Let me know if you detect puffs of smoke wafting from the computer case.

It is easy to convince people of something, but hard to keep them convinced.
                              Niccolo Machiavelli

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