Symptom: Your notebook runs only a few minutes when unplugged

Solution: Battery replacement

 Over their lifespans, lithium-ion batteries can lose the ability to hold a charge. After a few years, some batteries will last only a fraction of the rated runtime. Replacing a battery is relatively simple; most pop out from the bottom or back of the laptop.

Many retailers, however, charge hundreds of dollars for a new battery. Sites like batteries.com specialize in discount laptop batteries and can save you money on a brand new battery for your laptop. For example, a Dell Latitude D620 Li-ion battery costs $139 on Dell's Web site and $83.99 on batteries.com, as of press time. (The company even offers a two-year warranty and 45-day money-back guarantee on all laptop-battery orders.)