I am working on an old 486 ISA bus with a add in controller card. The card handles the hard drive (one channel) the floppy, the serial ports (2) and a game port. The hard drive is an Seagate AT 350 meg MODE 1 the CD ROM is a newer Sanyo 8 speed Mode 3 . The PC is set up with an 1993 Mozart sound card and an old no name sound card IDE controller. The CD ROM has been upgraded but is still plugged into the old sound card controller which was original for one of those one or two speed proprietary drives. I know that this add in controller will not be able to differentiate between Modes and there is a potential to slow down a hard drive but since the CD is Mode 3 and the hard drive is Mode 1 then maybe it would be better to just slave the CD ROM off the hard drive. and get rid of the separate sound card \ controller card altogether......or would this be a mistake ? .....would I be slowing things down with this configuration? Thanks Mark [log in to unmask]