SATA drives Boot configuration in BIOS

Hello,Hello, i have the following issue: I have 2 SATA HD installed on my desktop. Both recognized in my computer and the computer boots up fine. Each is a clone of the other. One is a smaller 40gb and the other is a 165 gb. The larger drive(denoted as letter E in disk management) is labeled active...the smaller drive(drive C denoted as healthy)
I want to be able to go into BIOS and flip the boot sequence should i need to...should the active drive fail one day.
That's where the problem lies...when I went into Bios there is a column on the left displaying both SATA O and SATA 1 drives however, under Boot sequence in the right hand side 2 SATA drives are not displayed ...it only displays SATA hd and then floppy and then i believe cdrom
How do I get both SATA drives to display under boot order? They are both detected in BIOS by the way ...both enabled as "ON". Each is detailed as to GB and so forth...In the left hand column there isn't any way to flip-flop the order...can only highlight by up and down arrows....any help is appreciated.