What happened to DVD writing?

Zaphod Beeblebrox zbeeble at gmail.com
Mon Sep 21 01:12:26 UTC 2009

On Sun, Sep 20, 2009 at 4:35 PM, Richard Mahlerwein <mahlerrd at yahoo.com>wrote:

> 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.

This is not necessarily odd.  The CD burner is one of the highest draw bits
in your system... save possibly your CPU and/or graphics card (depending on
what they are).  I have found that various DVD drives have been very
sensitive to power supply voltages and fail to burn properly when they're
marginal.  Your description here seems to point in that direction.  If it
works in computer B, try using B's power supply for A --- or maybe B has
other lighter draws.

Power supplies can also degrade over time --- especially if you have some
cheap capacitors in there.

I find the DVD drive is often the canary for spotting power supply problems.

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