This are two differnet problems. The second one is the spurious IRQ7, which is annoying, but harmless. The first and major problem is that the Linux kernel expects its root system on the device with major device number 0x16, minor device number 0x03, i.e. IDE secondary master, partition 3, commonly known as /dev/hdc3. This may be the hardcoded default compiled into the kernel, or it may come from a "root" parameter passed by the boot loader (grub, lilo, syslinux, ...). If the system uses SATA, and you have fiddled with the BIOS Setup or the Linux kernel, the kernel may now see the same partition as /dev/sda3 or /dev/sdb3 due to SATA support. For a system with only one hard disk, the disk is typically /dev/hda or /dev/sda, and the third partition on it is called /dev/hda3 or /dev/sda3. So tell the boot loader (at the boot prompt) to append a "root=/dev/hda3" or a "root=/dev/sda3" to the current boot options. If Linux is really on a second or third disk, use /dev/hdb3, /dev/hdc3, /dev/sdb3, /dev/sdc3 instead.

Alexander