Is the drive being recognized in BIOS setup? Did you change the boot sequence in BIOS setup to put the CD first?

 

Ron 

See this

 

http://support.dell.com/support/edocs/systems/xlob/dtg/en/systemse.htm#wp1211060

 

Read how to enter the bios, then make a change to your "Boot order" move the internal HDD to the top of the boot order, save changes on exit of bios.  Scroll down to "Changing the Boot Sequence"

F2 at post to enter the BIOS and Boot Sequence.  Drive 0 (zero) should be your first boot device.

Are you sure that you reconnected the drives properly?

 

Inspect the data cables on both drives and ensure that you also hooked up the power connectors as well.

 

Is it possible that you had a disc in the drive during the time you did your troubleshooting?  Sometimes the system will look for a disc if you remove it prematurely from the drive.

 

Have you tried accessing the system setup utility to change the Boot Priority to a different pattern and save it?  Try to reset the Boot Priority Order to a different order, save it, and then access the setup utility again and reset the original boot order to see if that fixes the problem.

 

To access the setup utility, press the F2 key when you see the Dell Splash screen.

 

 

Not sure if these are ISE or ATA drive but IDE cables are usualy marked which connector goes to which drive.

If you haven't already tried it, try clearing NVRAM. Power off and disconnect PC from the wall. Press/hold power button on the tower for ~15 sec. Open the case and remove the battery from the motherboard. Press/hold the power button again for 30 sec. Reinstall the battery (right-side up!), close the case and boot the system.

 

Ron 

 

 

That is also good advice Ron!

 

 

Ron,

  Thanks for the solution.  I must have had a brain cramp, because I've changed boot drives in the BIOS before.  Somehow, my external backup drive was moved up to first in the Boot Configuration.  Very simple fix.

I'd like to thank all the others for their quick replies.

:)