What does Seagate Disc Wizard have to do with anything? It sounds like you have a fully functioning computer, to which you are trying to simply add an older Parallel ATA hard disk (the kind with the 40-pin connector.)
Have you used an adapter to connect the 40-pin PATA drive to a SATA interface? Is the adaptor powered? Is the drive powered?
Have you verified the drive is set to the manufacturer's designation for a single drive running on a PATA cable, or in the case it's not alone, is the Master / Slave set correctly for it's cable position, or in accordance with the other drive's designation?
Have you gone into BIOS and confirmed your PATA controller on the motherboard is enabled?
Have you verified that BIOS is indeed seeing your PATA drive?
Is your boot order set correctly so the machine does not first try and boot from the XP installation rather than the Windows 8 installation?
Just a few thoughts. Get us some more information so we can get you going!