after enduring years of rough usages from myself and the previous owner, some screws have fallen out. i need to know what...

as for performance, i would recommend keeping drivers updated and removing system bloat. a defrag will do wonders if you havent switched to an ssd. plus, if you're really ambitious, linux mint can be a nice lightweight os. as for battery capacity, press f12 on boot and there is a self diagnostics mode which should show the remaining capacity of the battery. if its below say, 50%, id probably replace it