When you install two drives, you have to set one as a master drive and the other as a slave. The computer looks for the operating system on the master drive and uses the slave as a secondary drive that behaves as storage.
Change Jumpers on hard drive. jumpers that do exist on the hard drives are labeled "SP", "DS", and "CS", in that order. DS means "drive select" and is used to set the drive as master. SP means "slave present" and sets the drive to slave. It is used when another drive is set to DS. CS is "cable select". CS is only used in systems that support the cable select feature. Cable Select allows for each IDE disk drive to be jumped the same. Their position on the cable determines the drive ID. This requires a special cable, and both drives on the interface have to support this feature for you to be able to use it.
I think you should set SP jumper on your windows XP hard drive.