1. Random Access Memory (R.A.M):
This component of the computer system is very important /must use in the computing world. When the RAM is not good or working very well, You will start to get FATAL ERROR EXCEPTION messages. It is usually caused by disparity of the microprocessor. This mostly means RAM needs a new replacement.

2. Incomplete/Incorrect BIOS settings:
Every Computer system has a motherboard assigned to it. The most common way to access this settings is the by pressing the F2 or DELETE button few seconds after starting the windows screen. It is always advisable to be always careful when making some changes in the BIOS settings Menu.

3. Poor Power Supply:
As we all know that Our country is still struggling hard when it comes to regulation of Power Supply. In this case, There is a possibility of The Power Supply Coming Up with a Power Surge. To prevent this, It is highly advisable to Have a Very Good Uninterrupted Power supply (UPS) and a Stabilizer. It will help in stabilizing the ill flow of current.

4. System Overheating:
It is a must for every computer PROCESSOR to come with a cooling fan. Hence, if the cooling fan is not working well, It will Probably Start system overheating. It is very common to chips that are over clocked at higher speed. The best option is to Get a new if possible a bigger fan to be placed on top of the Processor.

5. Hardware Components Clash
This is also a major reason why Your computer might crash. Every hardware components converse to other components through an Interrupted Request Channel (IRQ) which is also unique to each device. It may crash when a user wants to use 2 or more component at a time.
To check the hardware clash,
Go to the Start Button, Click Control Panel and finally Locate Device Manager. If a device has a yellow '!' appears next to its description in the Device Manager, It means there is a problem. The most favorable way is to Remove the problem component and reinstall it.

Source:
http://www.gidimasters.com/2016/02/5-reasons-why-your-computer-might-crash.html

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