Just in case anyone else has this problem and doesn't want to spend an hour figuring it out...

If you are loading Windows XP onto a computer with a serial ATA (SATA) hard drive, you will have to manually load the SATA drivers.

As suggested on this usenet post, you need to put the drivers on a floppy disk.

Copy the drivers from motherboard support CD *\DriverDisk\SATA\*.* into root directory of floppy disk. (i.e. root directory of floppy disk should contain \pide and \sata folders, txtsetup.oem, etc. files.)

Then, boot system by Windows XP installation CD, when the message "Press F6 if you need to install a third party SCSI or RAID driver" shows up, press "F6". Then, press "S" to specify additional device when next screen pops up. Put the driver floppy disk you made in and press enter to continue. If the floppy disk is made successfully, the installation program will ask for selecting driver. Please then select "VIA Serial ATA RAID Controller(Windows XP)".) After SATA driver loaded and Windows XP can recognize the SATA HDD, you can continue to install Windows XP as usual.

This should work fine if you have the drivers on a CD somewhere.

Here's what not to do:
1) Pull floppy drive from another computer
2) Get lazy and not install the floppy, simply hang it by cables on the side of computer
3) After using floppy, allow the exposed circuitboard to touch the case
4) Watch smoke come from the floppy drive since the power was shorted out
5) Toss floppy drive in the trash