Reassemble the notebook and you're good to go!
You may want to upgrade some components to give your freshened-up laptop a performance boost to match, especially since you'll already have the machine open. Replacing major components like a CPU or GPU isn't really possible, but adding more RAM and moving from a traditional hard drive to an SSD can also be very effective upgrades.
Adding more RAM to your laptop is normally as simple as replacing the existing SO-DIMM (or DIMM) memory modules with ones of larger capacity, or by installing a second memory module of similar speed and capacity to the first if there's an open slot. PCWorld's guide to adding RAM to a laptop can help if you run into trouble.
Upgrading the notebook's hard drive to an SSD can be a bit more difficult, especially if you want to clone your OS and data over from a hard drive, but PCWorld's guide to swapping out your laptop's hard drive for an SSD has you covered.
Notebook computers can be cleaned and upgraded — with the proper planning and care. It's certainly worth your time to tinker before sending it to the e-waste bin. The laptop you save could be your own.
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