Dear Chris, I have seen all the top 5 tips and I have decided to pitch in to the community and give some of my own.

1. Keep your computer in an open area and make sure that the fan/fans for your computer have plenty of breathing space.
2. Don’t abuse your computer by installing an operating system that requires more RAM than the computer currently has, or fear the pain of a slow computer.
3. I highly recommend that you purchase a UPS (uninterruptible power supply) for your computer. This will keep your computer from crashing during power outages, and will protect your computer from low and high voltage occurrences.
4. Use a virus checker regularly. Everyone should use a virus checker. The best type of protection is continuous monitoring from a dedicated anti-virus program.
5. Keep a backup of your system handy! If by any chance your hard drive breaks, its always a great idea to keep a back up of your computer in case.