The computer BIOS will decide which will be read first.
Did you install Windows XP to the hard drive? New hard drives do not come with an operating system; to boot from it, you have to install one on it.
Yes. They hide in the boot sector program of a hard drive or floppy disk or in the master boot program in the Master Boot Record.
No. It hides in the boot sector program of a hard drive or floppy disk or in the master boot program in the Master Boot Record (MBR). Don Gus
A recent Mac with an Intel processor can boot from a USB 2.0 Hard drive. Earlier Macs could only boot from a Firewire Hard drive. When you turn on the Mac hold down the Option (alt) key. This will cause the Mac to scan for all available bootable drives. Select the one you want to boot from and it will start up from that drive.
Cable Select or by the jumpers put on the hard drive
I would suggest installing windows on one hard drive, then installing ubuntu on the same hard drive. Use the other hard drive for the backups (partition it).
Both internal and external hard drives can be removed from a computer provided that the PC does not boot from any of them. In that case, the first boot device would have to be a removable drive like CD-ROM/DVD-ROM or floppy drive.
If they are on separate hard drives you can generally just delete/format the hard drive with the OS that you do not wish to keep. If they are on separate partitions on the same hard drive you may have to reinstall the bootloader after deleting/formatting the partition.
It is likely to depend on the speed of the external hard drive, although most newer external hard drives have a reasonable speed, so it is likely you will be fine wi th using an external hard drive.
A CD-ROM drive is not needed to boot the computer. Just put the hard drive first in the boot order in the BIOS.
Most systems today have F10/Esc key into a boot menu at which time you can choose which hard drive to boot to, this works but there are better ways with a boot loader/manager. Lilo/magic etc...
How do you get a computer to boot up with no hard drive? What are the steps or what is the process of getting a hard drive installed into your computer if it is not bootable because of a missing hard drive.