[Zues]

Could be damaged ram or damaged ram port, try taking one out and starting the pc then taking out the other ram and starting the pc if it has two ram cards otherwise if you only have one take it to the repair shop and ask them to test the ram and ports.Could also be the motherboard and thousands of other reasons but its most likely the ram or motherboard.I built a computer a week or so ago and it did the same like yours and turns out it was the motherboard so I hope for you its not the motherboard cause I had to buy a new one and now it works.