The HD in my Dell R5400 failed so I replaced it with a WD1002FAEX and re-install Windows XP from the Dell re-install disk. At the point in the XP install where is asks to you to press F6 and install third party drivers I skipped over it.
Now when I look in Device Manager I see both the Ultra ATA Storage Controller and the SATA AHCI Controller are installed. They are dated 2007 and 2008 which is OK for XP.
Under Disk Drives the WD1002FAEX driver is the Windows Standard Disk dated 7/1/2001. My question would be is there a later driver for the WD1002FAEX? Am I losing perfermance with this old Windows driver. The BIOS shows SATA disk 0 is AHCI controlled.