I have a motherboard with four sata ports. I have connected a sata dvd drive in sata port 0. I also have 2 sata hard disks connected to sata port 1 and sata port 2 i.e 320 GB and 1 TB. The 320 one was installed first with windows and the 1 TB was added later on after 3 months. Now i want to install 2 os i.e. both windows or one windows and one ubuntu one on each hard disk. Now what should i do to enable me to choose which hard disk the motherboard should boot from. It is easier in IDE hard disks due to master slave settings. Howerver in sata there is no such choice. I have tried alternating the connections of the hard disks between sata 1 and sata 2 ports but the motherboard always boots from the 320 hard disk. Kindly advice regarding the same and whether making one hard disk primary and the other secondary will solve my problem. Also how to make or change a hard disk primary or secondary.