We will need a Philips screw driver and a small bowl should do. We will put extra screw in the bowl to not lose any.
Step 1: Remove Cover
First you will want to remove the case cover, the case cover should be on the left side of the computer and will be a small sheet of metal or a window to look in. Depending how tight the pins are on the back of the computer, they could come off with the use of fingers instead of the screwdriver. Go ahead and pop the case cover off and place the screws in the bowl.
Step 2: Take Out and Replace CMOS Battery
Now that the cover is removed, find the CMOS battery. It will be a small silver battery located on the motherboard. Remove the CMOS for about 10 seconds. Replace the CMOS and try booting up the computer.
Step 3: Ram Removal and Replacement
Try removing one stick of RAM at a time. Simply push on the back of the RAM until a clicking noise is heard signaling it is no longer locked into the motherboard. Pull on both edges of the stick to ensure nothing will break. Cycle the RAM in the computer to only use one at a time and see if it boots up.
Step 4: Graphics Card Removal.
Remove the graphics card and blow into the connecting port to remove dust or pathogens that could be affecting communication to the computer. The graphics card is a big black box sticking outward with HDMI and other connections on the back, it should also have a fan on it to help make it easier to identify. Replace the card and boot up your computer.
Step 5: Booting From Another Drive.
Moving on, try getting a USB stick with windows on it and
try launching off of that. To reach the boot menu, hit the power button and press f2 for a few seconds. The key is f2 may change depending on the computer you have. Once in the new screen called a bios click down on the boot menu drop down and launch off of the newly connected USB.