The most common top 10 computer troubleshooting and their tips to fix that problem are as follows.
1) The computer is unable to start up If the computer does not turn on when you press the power button, the following suggestions may help you to determine why the computer will not start up: Check the computer is plugged into an AC outlet properly. Plug another electrical device into the outlet to be sure that the outlet is providing adequate power.
2) The computer screen is blank.If the screen is blank, the computer may not be set to display the image on the computer screen. First, check if the monitor plugged in to a power outlet and is connected to the computer securely and make sure the monitor power button is on. If the power light is not on, it means that the outlet is not delivering power to the monitor.
3) Trouble with video card. If the power light of the computer and monitor is on and nothing comes up on the screen when you start your computer then there must be something wrong with video card. You should take your computer to a repair shop or change its video card with the new one.
4) Software is functioning abnormally. If the software is unresponsive or responds abnormally, follow these tips. Restart your computer and run a virus scan. For this purpose you should have reliable antivirus software installed on the computer to fix this issue.
5) Windows do not boot properly. If windows do not boot properly then you should have reinstall windows with the windows recoverable CD.
6) The computer is on but not responding. If the computer is turned on but not responding to software or keyboard commands, then it must be freeze or halted....