You want to get rid of an old computer -- but that device doesn't have to end up in a pile of old e-waste just yet. You have numerous outlets for selling your old computer, though the one you decide upon may depend on how much time and money you're willing to expend.
Local and International Options
Before you sell the computer, transfer old documents to your new computer, to an external hard drive or to a cloud storage program. Then wipe the data from the old computer using any number of downloadable drive-erasing tools. Next find out how much your computer might sell for. Run a search on sites such as eBay and Craigslist to see what other people are asking for computers like yours. Also take a few photos of the hardware. To start selling, post a few photos of your computer on your social media feeds, letting your friends and associates know you're selling. Also create an ad on Craigslist, where you won't have to pay any fees or even pay for shipping -- Craigslist encourages local, cash sales only. Also search for computer resale stores in your area that may be buying. If you don't have any luck locally, post an ad on eBay. You'll have to pay for shipping and pay a seller fee when it sells, but you'll have a much wider customer base than if you were dealing locally.