When you want to add memory (RAM) to your computer there are some things you need to know:
Is your computer still under warranty? If so, you need to find out if installing memory will void your warranty or not.
How much memory does your computer have currently?
How many memory slots does it have?
What is the maximum amount of memory that your computer will support?
Once you know these things, you have to find out what size and speed of memory your machine will support.
Then you will want to find out what is involved with installing the memory into your machine. Some computers are built so it is very easy to install memory, while others are much more difficult to upgrade.
Good Luck with your upgrade!