Well, I've managed to get this CD writer to write 421MB w/o having 421 MB temporary space. It seems that if the feeding program (producer) doesn't keep up with the writing program (consumer), it will stop the burn. I still have both the hard-drive and the CD writer on the same IDE controller. Do any of your computers have the same configuration (same IDE controller)? I'm wondering if it's worth the trouble of putting them on separate controllers. Thanks.