Computer won't turn on (After adding RAM)

If you recently added a new hardware (e.g. a new RAM memory stick, hard disk drive, graphic card etc.) to your computer or replaced an old hardware component, remove it from the computer in order to check if that is the culprit that prevents your computer from turning on.

If the computer does turn on, either the new hardware component is broken or it is incompatible with other hardware components of your computer.

Check if the RAM memory stick(s) on the desktop computer/laptop is (are) inserted in the RAM slot(s) correctly and in the correct slots (according to the motherboard's manual). A faulty or incorrectly inserted RAM memory stick(s) may prevent the desktop computer/laptop from turning on. 

If you don't know how to remove and insert RAM sticks, read these useful article:

Laptop (by Dummies) or Desktop computer (by Howtogeek).

Maybe the new RAM stick you added is incompatible with the one which is already inserted in the computer. If this is the case, all you need to do is take your old RAM to a computer shop and ask them for a compatible RAM stick.

Note: If you didn't manage to find a compatible stick with the old one, consider buying a RAM stick set.

Maybe there is something wrong with the computer's CMOS settings. In this case, all you need to do is to reset the settings and after that your computer should start working.

These are two common ways of clearing the CMOS settings:

1. Via the CMOS jumper
   
   Turn off the computer and unplug it from the power cord. Then, open the computer’s case and locate the jumper named in one of the following ways: CLEAR, CLR CMOS PASSWORD, CLR PWD, CLEAR CMOS, etc., most often located near the CMOS battery. Then, unsit the jumper from the current position and set it to “clear” position. Then, turn on the computer and turn it off after a short period of time, and after you turn it off (and unplug in from the power cord), reseat the jumper into the original position.
   
   This is how a jumper looks like:
   

   
   
   
   * Not all motherboards have clear-CMOS jumpers.
   
   

2. By reseating the CMOS battery
   
   The CMOS battery is the one which provides the power used to save the BIOS settings (among which time and date). So, all you need to do is to remove the battery and reinsert it after a minute or two and the CMOS settings will be cleared. Be very gentle when removing the battery in order to avoid damaging its socket.
   
   

   

   
   * Not all motherboards have removable CMOS batteries. If the battery won’t come loose easily, don’t apply force to remove it.

if the RAM slots is clogged with dust, the motherboard won't be able to recognise the RAM stick. All you need to do is to clean the RAM slot and then reinsert the RAM again.