mount command is only going to show partitions that are mounted based on the configuration in /etc/fstab. Not knowing your system I guess you already have a sata drive in it and using it under FC7. If so to see if the system sees the drives use this command as root. ' /sbin/fdisk -l '. Guessing you already have a sata drive and added two addtional drives I would say you see the following /dev/sda /dev/sdb, and /dev/sdc. If so post the output of fdisk command and what you want out of the drives when done.
Distribution: RHEL 5.1 with Pieces of this and that.
Kernel 188.8.131.52, KDE 3.5.8 and KDE 4.0 beta, Plus Development src.rpm, ATI fglrx64_7_1_0-8.433-1 rpm with 3D and DRI working.
Acer 5100-5840 with webcam, ati, sdcard reader, sound, atheros based wireless, all working. Only thing not working is the memory stick reader.