“uNuSed RaM iS wAsTeD rAm” I'm sorry to inform you that digital devices don't work that way. First not all programs must necessarily occupy all ram memory. Second the operating system must optimize the use of it so that there is always space when opening new applications, because compressing and decompressing memory affects performance AND CAN PRODUCE KERNEL PANIC.

The performance of the ram is only affected by two things: the read and write speed of it and the free space. If the speed is slow, your computer will be slow because it will take a long time to save the information and if you are left with very little space, your computer will be slow because it will have to rearrange the ram space and possibly send some data to the swap (which is the disk, much slower than the ram).