How do we know the computer could not start due to RAM problems?
If the computer does not have any problem, we can hear the sound of one Tit! when the computer is first turned on. But, if there is a problem with the RAM, you could hear Tiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiittttttttttt! Tiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiittttttttttt! Tiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiittttttttttt!, repeatedly. Do not be confused with the sound of one Tiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiittttttttttt!. If the sound heard once, it tell it is not RAM problem, but VGA or monitor the problem.
Sometimes the computer cannot be turned on and there is no sound at all. Only the cpu fan and the power supply fan is running. Remove all the RAM and turn it back on. If there is Tiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiittttttttttt! sound heard repeatedly, it is mean there is problem with the RAM. But if there is still have no sound heard, then there might be other things that are damaged.
One more thing to see is the computer got not enough RAM, but as it should have. It have 1 + 1 = 2 Gig RAM. But in the system properties window it is only show 1GB. This means that there is only one faulty module and another one module is not damaged.
Not all faulty RAM can be repaired using pencil eraser. The one which can be repaired is when it has dirty contacts. The dirty contacts will make the problem as I wrote earlier. The contacts can be cleaned by rubbing the eraser on the contacts slowly and repeatedly.
