Here are some tips and idea to follow on how to solve ur laptop problem

1)In a situation where by your PC or laptop offs while working...
.....1)check if the fan is active
2)check if the paste on the processor is not dried

2)..when ur laptop shows no bootable device
.......1)check if the hardware is properly inserted or damaged

Note this: once your hardware falls on the fall it is damaged finally without no solution u av to get a new one

3).....How to upgrade your laptop
...there are various ways to upgrade and format ur laptop .....
For u to upgrade or format you must have a minimum ram of 1gb
Now this is a way to upgrade 

I recommend u use CD ROM

Lets start with formatting

To format
Since you must have a minimum value of 1gb ram

Get windows 8.1/ window 7 (recommended CD ROM disc ....window 10 can easily contact virus which is not recommended

1)after getting d windows disc
2)on ur laptop let it to be plugged with power
3) open ur CDROM compartment
3)insert ur windows CD
4)force shut d computer by holding d power button down
5)on ur computer 
6) immediately ur computer is on
for users of HP press F9 
For users of dell press F12
For system like Packard bell and others F12
For system with no name press Escape key ESC

7)when u press it continuously
It loads and shows windows
Cool for d first phase u chose your language and press next
9)for d second step accept terms and conditions
10) for d third step you will see something like

Upgrade(for u wu don't want to format but upgrade to higher version)

Custom advanced settings (for does wu want to format)
Choose btw dany 1 depending on wat u wanna do

Let me choose custom advanced settings
Wen I click on it
I see something like disk partitions( this contains d file on ur hard disk) if d files are relevant remove ur hard drive and use external harddrive to copy ur file to anoda system 
If irrelevant delete dont remove ur hard disk
So by d down u will see advanced 
Delete those files

11)click on next ...so d system will install some features so at a certain pointvur laptop will switch off and on back ...don't touch anything let it continue 

After installing everythingbur system is like a virgin wit nice look

This ain't d end
After formatting

Get ur drivers pack 14 from any computer engineer
Load d CD so ur computer tends to bring out d files that are not drived drive them all

The purpose of driving is to allow d PC to run smooth



***************


Wen ur computer proves slow
Change d ram to higher version


Note never leave d power battery
Unremoved wen u wanna keep ur laptop for a longer period of time


Ur laptop can work without battery

Remove ur battery 
Plug ur charger into d laptop and connect d charger to NEPA light
It works



Thanks for reading more to come