there should be an option in the BIOS that says "Halt on" listing Floppy and Keyboard missing.
yours must have the option for IDE HDD too.

rubbish. the BIOS does not need SATA to be in IDE compat. mode to allow native SATA HDDs. XP will install straight to a fresh SATA HDD without needing drivers, especially not RAID ones.
If you notice the first part of my reply was based on the windows XP problems with SATA (which was a mistake on my part when first reading the original post)

I've not come across an XP install that will work straight to SATA drives without either a bios setting which makes them appear as IDE in some manner* to windows, or a driver.
My P4P for example will make the main SATA ports appear as Third IDE Primary and Forth IDE Primary to let XP install on them without additional drivers*.
Set them to RAID mode and you then need additional drivers.
That however is probably irrelvent to this problem as I realised when I put in the latter part of my original post
However it's got to be a bios problem given the timing of the message, in which case the latter part of my first post applies, the need to stop the relevent controller from looking for an IDE drive, which means either the machines main BIOS, or if it's got something like a SIS, Promise or other third party chip giving it additional drive controllers compared to those on the main chipset it is likely to have a secondary bootable bios for that (which the main bios hands over to for a check).
I would check the boot order to make sure it's not referencing any IDE disks in the boot order, or any "raid" controllers (I can't remember how exactly they often refer to them, probably "additional driver controller" or "raid controller).
If it's referencing a raid controller or similar the op may need to enter an onboard secondary drive/raid controller's bios (they tend to have their own mini bios to allow them to be bootable, in the same way that SCSI/raid expansion cards do).
To access the secondary (raid) bios, if it's there you normally have to let the system boot past the main bios then when it mentions something about "promise" "high point" or "sis" hit F4 or whatever key it asks for.
*It's making them appear in a backwards compatibility mode for ease of use (SATA wasn't around when XP was developed so has no drivers on the standard XP disk, hence the fudge on things like Intel chipsets with integrated SATA).