What happened to DVD writing?

[Warren Block]

On Sun, 20 Sep 2009, Richard Mahlerwein wrote:
>>
>> This drive has probably written under 50 DVDs, all ISOs used for backup.
>> It's a Lite-On DH-20A4P bought in August 2008.  It's looking like the
>> drive itself has failed.  Which seems odd, since I thought it could
>> still burn CDs.
>
> I have had several exhibit behavior even more odd.
>
> The most unusual was this particular CD writer... It read both DVDs 
> and CDs but would write neither (it had worked fine the week before).  
> I took it out of the drive bay and hooked it to another PC to test and 
> it worked fine there.  I put it back in the original PC and it 
> failed.  I was swapping things around on that PC (assuming bad cable, 
> bad power, etc) and had it sitting loose on the desk and found that it 
> now worked again.  Put it back in the drive cage and it again would 
> not write, though reading was fine.  Anyway, I finally figured out 
> that even slight pressure in on the sides where it mounts would make 
> it fail to burn CDs.  The cage itself exerted a bit of pressure and 
> that was enough to make it fail at any attempt to burn a CD.

It does appear to be hardware failure.  A web search suggests that this 
drive has two separate lasers, so DVD writing failing while CD writing 
still works is believable.

Sorry for the noise, and thanks to everyone for the suggestions.

-Warren Block * Rapid City, South Dakota USA