Red Hat Enterprise Linux 4 Update 3 and CentOS 4.3 do not detect the 3ware Escalade 9550SX and 9590SE RAID controllers.
RHEL4 Update 3 and CentOS 4.3 require an updated 3ware device driver for installation. Both 32-bit and 64-bit driver images can be downloaded here:
http://updates.aslab.com/isos/RHEL4/
After the driver image has been downloaded, create a driver CD using the following command:
# cdrecord -v
To install the operating system, boot from RHEL4 Update3/CentOS 4.3 CD #1. At the prompt, enter 'linux dd'. The installer will ask for the driver disk.