I encountered this same problem when I purchased a new motherboard. See post...
You can either buy a IDE to SATA converter for your DVD drive, as the responder suggested to my post, or I found a more unique solution that proceeds as follows...
1) Install FC5 from your IDE DVD drive using the all-generic-ide irqpoll pci=nommconf
2) Create at least three partitions in the hard drive during the FC5 install:
a) LVM partition for FC5
b) ext3 partition to store F7 files to perform hard drive install of F7
c) free space available for LVM partition where F7 will install
3) After FC5 install, transfer F7 iso file to the ext3 partition, as hard drive installation can only proceed from an ext3 formatted partition
4) Read the hard drive installation instructions closely before attempting, as it can be tricky for the first time at...
5) Create a dual boot for both FC5 and F7, as you will only be able to access your ide drive through FC5.
Don't ask me why Fedora dropped support for mixed drives in F7, but from what I understand there are kernel issues. Fortunately, Fedora is the only linux distribution I could find to perform the hard drive install on an AMD 64 motherboard.