you can try multiple setups:
assuming u currently have 1 HD and 1 Cd/DVD-drive
1) put the CD-rom as primary slave on the same channel as you HD
2) put ur Cd-rom as secondary slave (not reccommended if its on its own)
3) put HD and CD on primary channel and jumper both to cable select (CS or Csel)
TheMajorMMX - Intel P200 MMX @ 225Mhz - V-Tech (PcPartner) Baby-AT mb w/ Intel Triton TX chipset - Nvidia Riva TNT2 M64 w/ 16MB - 256MB M-Tec SDRAM - Still running.....