PROBLEM WITH DETECTION OF 2ND HDIVE AFTER NEW INSTALL

My system now has two SATA internal hard drives-Western Digital 500 gb and a
Western Digital 160 gb. I cloned a copy of my original hard onto the new 500
gb hard drive.BUT with both drives installed I could only boot from my
original 160 gb hard drive.

Obviously, I wanted to use the new hard drive as the Master and the original
as the Slave for storage.But SATA doesn't accomodate this approach.NOW I
could disconnect the original hard drive and boot from the new . I would not
have a bacdk up\storage hard drive, however.

I tried changing driving names through renaming by altering registry values.
I could not rename the drives through MY COMPUTER\MANAGE\DISC DRIVES\RENAME
LETTER OF DEVICE. The drop down menu didn't offer the letter "c" for the new
drive and the only letter offered to select for my original drive was "C".
The changing of names through altering registry values crashed my system.

PRESENT STATUS OF MY SYSTEM: Boots and operates form new 500 GB disc drive.
Original hard drive is recognized in Setup. HOWEVER, if I enable both drives
to be run by SYSTEM BIOS as controller my computer won't boot. ERROR MESSAGE:
No boot device. If I TURN OFF the SATA controller for the 160 GB disc drive
then my computer boots up.

The second hard drive (160 GB drive i want to use for back up) is not listed
in My Computer or Device Manager.In the BOOT MENU I only have one
SATA drive disc device listed to select as primary boot. I can select to
boot from a floppy diskette, even though I don't have a floppy disc, or an
IDE hard drive, even though I don't have such a hard drive. I have selected
SATA hard drive as the only option (1) in the boot order.

When I turn off the 160 GB secondary drive its system controller changes f
from SYSTEM BIOS to unidentified SATA CONTROLLER.

DELL DIMENSION 3100 -e310 BIOS Dell System DV051 version A04
Phoenix ROM BIOS plus version 1.10 A04

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Many thanks and sincere gratitude to anyone who takes the time to answer my
query.
Sincerely,
Chris
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