End users generally shouldn’t repair power supplies. They are a consumable, wearable part that requires expertise to safely repair.
Repairing a Dell speaker bar that had no audio.
The Lenovo X220 can have a second “slice” battery that snaps onto the bottom, adding nearly 60 Watt-hour to the 86 Watt-hour 9-cell battery.
Lenovo sends repair parts to you if you want to fix your laptop on your own.
Apple hardware doesn’t always play nice with others, their CD/DVD drive is a perfect example of not working with PCs.