Serial Advanced Technology Attachment (SATA) hard drives are a common type of internal storage device used in desktop computers. Many new computers come with a SATA drive installed as the main hard drive containing the operating system, but most motherboards have more than one SATA port, which allows for installation of additional SATA drives. Installing a second SATA drive will require an additional SATA interface cable and power connector, but the installation itself is relatively easy.
Turn off the PC and unplug all cables.
Open the case with a screwdriver. Most cases have several screws along the right side of the back of the case that will allow the case to be opened.
Locate an open hard drive bay. Hard drives are mounted in bays that look like rectangular spaces in metal housings that are usually located at the front of the case. Look for your current hard drive; there should be a free bay next to it.
Slide the hard drive into the bay with the ports on the back of the drive facing back, then mount the drive in place using the mounting screws that came with the drive.
Connect the drive to the motherboard using a SATA interface cable. The cable should come with your hard disk. Simply look at your currently installed SATA drive and plug the cord into the back of the new hard disk in the same orientation, then follow the SATA cable of your current drive to the motherboard to locate the SATA ports and plug the other end of the cable into a free SATA port.
Plug a SATA power connector into your new SATA drive. Look for a power connector coming from the power supply (the big box-shaped device with a bundle of cables coming from it) that is identical to the one plugged into your current SATA drive, then plug it into the port on the back of the new hard drive.
Close the computer's case and plug in all the cords.
Start the computer. Many Windows-based machines will automatically detect the drive. If this is the case with your computer, you are finished, and you can use the drive normally. If you cannot see the drive, go on to Step 9.
Restart your computer and press the appropriate key to enter BIOS set-up. The key may be prompted on your screen; if not, check your user manual to find out the correct key to press (Delete, F1, F2, ESC, F10 and F12 are common keys).
Navigate the BIOS set-up system and instruct it to detect new hard drives. Each BIOS will be different; within the BIOS, there should be a list of key commands on the screen that you can use to navigate the menus. Look for a menu dealing with hard disk configuration.
Save the changes and exit BIOS. After you exit, your computer will start up normally.
On newer Windows machines the drive should be usable without going into the system BIOS.