dvd-rom can't read cd-r but dvd-r/rw can?

hello,
i bought a medion 1453 computer with a pioneer dvr-105 dvd-r/rw and an ide dvd-rom 16x. i backed up the files from my old computer (.txt .doc .mp3 .avi etc.) with the basic adaptec program onto cd-r's. the new computer recognizes both drives, but the dvd-rom drive will not recognize my backup cds -- only originals. is this normal or am i overlooking something?

thanks

 

old computer win98
new computer winxp
if that matters?

 

A bit strange m8 as I once owned a cd-rom that couldn't read cd-r(w)'s. Get the name brand of the dvd-rom and look for a possible firmware update....
The firmware page:http://forum.rpc1.org/portal.php

Shoey