How to Determine Your Power Supply for a Laptop
- 1). Turn your laptop over and look for the manufacturer's sticker on the back. Read the sticker to learn the voltage and amperage your laptop takes. For example, an IBM ThinkPad T30 takes a 16-volt, 4.5-amp power adapter. Also take note of your laptop's specific model number, which may be different from the series number printed on other, more visible parts of the laptop.
- 2). Go to the laptop manufacturer's website and search for your laptop's specific model number. After searching, if a products or parts page link appears, click on that. Look through the search results for a replacement power adapter for your laptop.
- 3). If no replacement adapter is sold on the manufacturer's website, find the part number for your laptop's adapter. An easy way to do this for a Dell laptop is to turn the laptop over again and write down the service tag number, which is printed on a small, white sticker. Search Dell's website using the service tag to find a list of part numbers for every part of your laptop. For other brands, look through the manual, parts list and specifications page to find the part number.
- 4). Many eBay stores list new and used laptop power adapters, including those for older or harder to find models. Search eBay for your part number and purchase one from a trustworthy seller. Buying from a seller with a return policy will save you headaches and money if you discover the power adapter you bought is not the right one.
- 5). As a last resort, universal power adapters also work for laptops. A universal power adapter has a variable voltage and comes with a variety of plugs that fit most power jacks. These are available for purchase from most electronics stores. Find the plug that fits into your laptop's power jack, attach it to the universal power adapter's end, and adjust the voltage to your laptop's specifications.
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