FC 5 can't fine CDROM during installation - Core 2 DUO motherboard

[Barry Yu]

During installation, the install CD booted up in CD ROM, Installation Method was Local
CDROM, up to this point, got message; Unable to find any devices of the type needed for
this installation type. Would you like to manually select your device or a driver disk? 
The system is with Core 2 DUO E6400 cpu, this happened to both Intel DG965WH and ASUS P5B
Deluxe.Both mother board were with Intel RAID controller. 
I tried using the win98 floppy to boot up with CD ROM support option, saw message; 
No drive found - aborting installation, 
No valid CDROM device drivers selected. 
No way to install the FC5 with above 2 motherboards, what was the problem?