I had 2 SATA Hard DRIVES in this configuration:

WD Caviar 500GB (WinXP) => Onboard SATA socket
WD Caviar 160GB (Storage) => Onboard SATA socket

I bought a new SATA HD & connected it to a PCI SATA card:

WD Caviar 500GB (WinXP) => Onboard SATA socket
WD Caviar 160GB (Storage) => Onboard SATA socket
WD Velociraptor 160GB (WinXP) => Adaptec1210SA SATA card

I couldn't get the Velociraptor to boot off the SATA card, so I swapped SATA CABLES with the Caviar:

WD Caviar 500GB (WinXP) => Onboard SATA socket
WD Caviar 160GB (Storage) => Adaptec1210SA SATA card (swapped)
WD Velociraptor 160GB (WinXP) => Onboard SATA socket (swapped)

The (WD Caviar) shows up in the ADAPTEC SATA PCI card BIOS but not in Windows Explorer or Device Manager (Adaptec card is in Device Manager), even after un-installing & re-installing the driver. I swapped the cables back & Windows sees all the drives. Why is the Caviar HD not appearing in Windows Explorer?

SPECS:
Motherboard - Abit AN7
CPU - AMD Athlon XP, 1666 MHz (12.5 x 133) 2000+
BIOS - Phoenix - AwardBIOS v6.00PG
HD #1 - WDC WD300BB-00AUA1 (27 GB)
HD #2 - Maxtor 6E040L0 (38 GB)
HD #3 - WDC Raptor (160 GB)
RAM - Crucial 767 MB
BIOS - Phoenix Award v6.00PG 06/13/2005I phoned Western Digital tech support & asked them why Windows could see the Velociraptor HD & not the Caviar. They said that the Velociraptor is setup for Raid & suggested I try a non Raid card. I chose the Promise SATA-300TX2-Plus.

http://www.promise.com/product/product_detail_eng.asp?product_id=138