I was playing a game on my computer when it would say low memory detected and it would shut down the game. I looked at the memory in task manager when it said that there is 4 GB or ram and one slot being used. So I turned off my computer opened it up and saw that one of my RAM cards wasn't fully in, so I took it out and put it back in and made sure it was in. When I started up my computer again it just started beeping at me like 4 times until it shutdown and started up again to do the same thing. I took out my RAM card and started it up again and works fine. What is the reason this is happening?