Replying from a convention to say that I think what you are looking for is "CPU cycles". RAM is memory, not computations. Nothing happens in RAM, stuff is just stored there until it's needed by the CPU, the reason complex programs need more RAM is because they have more information they need to keep stored "close at hand."

Think of RAM as a really convenient shelf right next to you with the stuff you need to use often and quickly. The CPU is you and each thought is one CPU cycle.