I found this in fedora forum
perhaps a clue at http://linux.derkeiler.com/Mailing-L...4-01/1782.html
"The RAID drivers are not loaded correctly by the Red Hat installer after following expert steps necessary to load disk drivers from a diskette prior to installation. After inserting the driver disk and selecting the appropriate driver, the Red Hat installer reports "no hard drives have been found" although the machine's hard drives have been properly installed and configured. RAID 1 configurations with 2 ATA/EIDE and also with 2 SATA150 drives have been tested."
Have a look around.
However - you should use PM only to free up space, not to create the extra partitions where linux is going to live. Let anaconda do that bit - makes the installation more likely to "take".
Even this way, you are not garanteed to keep all your windows data. Back it all up anyway. (Often you can back up to an ISP you know?)