1. To make use of slower media. If media is expensive locally, or if
the OP wants to make use of higher grade media without paying a
premium for it, lower speed media is a nice option to have. However,
if the drive doesn't support the speed, you'll typically get something
like an "unrecognized media" error if you attempt to use it.
2. The guy might have bought a spindle of media that the drive isn't
particularly compatible with or is of poorer quality. Burning at a
slower speed sometimes garners better results.
3. Maybe the guy just wants to relax a bit, rather than rush, rush,
rush. No. Wait. Nevermind. What was I thinking...
NEways, an 8X CD minimum burn speed might be the slowest you can hope
for. A lot of high speed CD burners won't go any slower than 8x or
4x, so it's not surprising to run across a DVD burner that does the
same.
As for the DVD burning speed, if the drive doesn't support the slower
speeds in the firmware, you'll have to wait for a firmware that
addresses it or just buy 4x media and live with it.
If it's just in Nero, it could be that it doesn't properly recognize
the drive. In the past, you could download an updated version of the
CDROM.cfg file (which contains CD and DVD burner IDs, and lists
capabilities) but I don't know if Ahead still lets you do that. If
not, you can manually edit that file to try and a proper entry for
that drive (look at the other entries for examples). The gotcha is
that the drive and its firmware must support these modes. While Nero
you can get Nero to offer these speeds to you, it's no guarantee that
the drive will let you do it.