As we mentioned, it's possible to dismantle a PC, take out the hard drive, and recycle the rest of the parts. But if you feel guilty about wasting the still-functional motherboard, memory chips and processor in your old machine, you can pull out the old hard drive with your data and replace it with a blank refurbished hard drive for as little as $16 [source: Newegg].
Installing a new hard drive really isn't much more difficult than plugging and unplugging cables and turning a few screws. The key is to replace the old drive with one that's the same type.
Today, most hard drives use a data connection known as SATA, but if you have an old PC, it might use an earlier technology known as IDE. You can easily tell the difference, because a SATA drive uses a pin-less, L-shaped connector, while IDE drives have a whole bunch of pins on their connectors. Make sure that you pick one with the same physical dimensions. Some big desktop systems use 3.5-inch (8.9-centimeter) drives, while more compact desktop PCs and laptops generally favor 2.5-inch (6.3-centimeter) drives [source: Smith].