Yes, I am a software developer, not a hardware engineer. I am not going to talk anything about hardware memory, I am going to tell you something related to a true software story, :D.
Since I went to college to study computer science, I always heard people saying, the more memory the faster. So I always believe that if you machine have more memory your machine will become faster, until this morning, I learnt something from my tech lead Badri . He says no to me, and explained all the reason. He totally changed the concept I brought from school.
The answer is it depends. OK OK, I am not tricking you. I will tell you why. For example if your machine has 4GB memory, and there is one app running based on Java, and it use all the 4GB. And suddenly your app memory usage boomed to 4GB, then GC starts, and your machine will be dead.
What does this mean? You should know that Java does GC as soon as it reaches the memory limit. The more memory you have the longer it will take of GC. If we only have 2GB memory, then it will take less time but frequent GC, will will reduce a lot of pain. So we should memorize this: It depends.