"codec" for Samsung CD-R/RW DVD drive

I installed a Samsung SM-352B combo drive on my Dell
XPS-R450, and it reads CDs fine. I haven't installed any
other software, but I assume it writes CDs OK, too. But...
when I try to run a DVD, an error message pops up that
says something about no compatible DVD codec. Is this
"DVD codec" a piece of hardware or software?

I was under the impression that no hardware was needed
in conjunction with this unit to enable displaying DVDs.
If so, where does one get the software codec?

Or is that ancient PCI card that came with the early 1999
Toshiba DVD-ROM player in my Dell Dimension still
needed as the codec?


FranklinWright