Thank you for your question. We have a tool on our website called the system scanner. It is software that runs on your system and tells you how much memory you have installed and also recommends memory that is guaranteed to be compatible with your system.
On the main page if you tick the box that says "I agree to the terms & conditions" and then click download the scanner. This will run the scanner on your system and tell you exactly what you need to know.
If you do have any questions at all, please don't hesitate to ask and I would be happy to help.