Choosing the Correct Drive Buy
Your computer has two horizontal drive bays and one vertical mounting position which hold up to three drives, as shown below.
vertical mounting
horizontal drive bays
Your computer may have come with a hard disk drive already installed in the vertical mounting position. If not, you can install one
If you are installing your first hard disk drive, it is best to install it in the vertical mounting position. If you add a second hard disk drive or diskette drive, use the lower horizontal drive bay.