Prepare For Failure
Sometimes the best computer hardware maintenance is preparing for failure. All of the expensive tools you use, from your car to your computer to your cell phone, will fail eventually, so you should start preparing to replace them—especially since they’ll probably fail at the least convenient time.
For computer hardware, the device most likely to fail is your disk drive.
I used to keep a spare disk drive handy in case on of my disks failed, but with the rapidly dropping cost of hard disk drives, I think it’s better to accept the inconvenience of driving out to buy a new one every few years.
After your disk drive, the following devices are most likely to fail. You either want to have a spare handy or at least the money available to buy a replacement:
Printer (they tend to stop printing correctly, rather than break entirely. It usually isn’t worth fixing a cheap printer.)
Computer power supply (often starts making noises a few weeks before dying)
Power button (if you’re careful, you can hot-wire most computers to use your computer until you buy a new button LOLz 🙂 )