Proliant DL140 - Using Embedded Raid on Redhat ES4 OS

[Van Thai]

I am trying to set up a RAID 1 (2x160GB SATA) disk on a DL140G3 using the embedded controller. I enabled the RAID in BIOS then use the HP Embedded SATA Raid Controller Utilities to configure and build an array. When the machine boots up it reports that one logical device(s) found and BIOS Installed Successfully.
I downloaded the latest driver from HP site, unzip it then dd on to a floppy disk.
I then booted up from disk 1 of ES4 using "linux updates dd" command and linux prompted for driver disk which I selected sda because I used an USB floppy drive.
However when the OS gets to the Disk partition set up, it reported "No Drives Found".

Please advise.