Learn How To Safely Throw Away a Broken Computer
All computers contain plastics, lead, metal, and other harmful materials which can harm the environment, so you just can't throw them out in the trash. It is also might be illegal for you to throw out used computer out with your trash.
The best place usually to learn how to safely throw away your broken computer is to ask your local government like city hall if there are places to dispose of old electronics, computers, and appliances.
You can also hand over your old computers to computer recyclers, so they can dismantle, and recycle your old computers.
In some cases, you can contact your computer's brand, and they might offer a free recycling program for you to recycle your old computers by shipping it back to them for recycling.
For ink cartridges and laser printer toner cartridges, you can usually recycle them at office supply stores which sell ink and toner, or you can contact the maker, and ask them to send you envelopes or boxes to send the used ink and printer toner back to them for recycling.
Instead of throwing away your broken computer, you could use it to make something useful by buying a copy of 62 Projects to Make with a Dead Computer: (And Other Discarded Electronics).