1989 Amstrad ALT-286 Laptop Reburbish / HDD Replacement / PC Speaker Repair

As a kid I got my hands on this (already old back then) laptop somehow. I played around a bit with it, then gave it to my sister. Recently she told me that it wouldn't boot anymore. I assumed, the CMOS battery was dead and replacing or charging it would solve the problem. How wrong I was :) The HDD was broken, and the PC speaker not working, but the CMOS battery was fine after recharging it.