I need to replace my SATA PCI Controller Card - How do I do it?

The system is a Dell Precision Workstation 650 Desktop (circa 2003).  It came with a 120GB SATA HDD that was connected to a Promise PCI SATA Controller Card.  I've installed a 2nd SATA HDD to it and got it to see the 2nd HDD by creating an array.  The HDD's are set up as Striped 1+0 RAID arrays.  The only quirk is that after the SATA BIOS runs, I get a message telling me to press either F1 to Continue or F2 to enter Setup to proceed to WindowsXP Pro.  The Bios on this machine is so basic that there aren't any options for the boot priority sequence and the Primary 0 and Primary 1 disks are listed as "unknown".  I can't figure out how to fix it to remove that message.

 

Anyway, I've been reading about RAID setups and I hope that I just didn't mess up my HDD configurations with this.  My goal on this PC is to have 2 independent HDD's  - the first is primarily for the OS and the 2nd is for pure data storage, so if the OS crashes or fails for some reason (un-repairable virus infection or hardware related driver failures...) I can reinstall the OS with all my data in the other partitions remain safe. This is how I've set up all my IDE based systems.  In what I have read about RAID, it sounds like the most basic RAID 0 (or the 1+0 that this Promise card uses) writes data across both drives, therefore, if one drive fails, ALL my data will be lost.  Is this true?  Am I reading the info correctly?

 

What will happen to all the data if I remove the 2nd HDD from the system?

 

I don't want to have anything to do with this RAID setup at all if this is the case. My goal  for this thread is to find out how to replace the RAID PCI SATA card with a non-RAID SATA card that I want to install.  The only way that I know how to install a SATA controller card is during a new install of the OS using the F6 key and the floppy, but I need to find out how to install the controller card without going thru Windows XP Setup.  I thought that I could just install the non-RAID card into an empty PCI slot and reboot and install the drivers that way, but the system locks up after it sees the 2nd SATA card and the system BIOS appears.