Here's the Microsoft link:
http://www.microsoft.com/athome/setup/addmemory.aspx
And here are a couple of links as to where to get the best buys on RAM:
For Desktop users:
http://www.ramseeker.com/news/where-to-buy-the-best-ram-for-desktop/
For Apple users:
http://www.ramseeker.com/news/how-much-does-it-cost-to-add-more-memory-to-your-apple-computer/
Both pages have lots of info on RAM for laptops, notebooks, desktops, etc.
I really need to study up, as I need more RAM. I am HOPING there is a portable UBS drive RAM booster, so I don't have to mess with the hardware! I am terrified of touching the hardware! lol
Later all~Donna
Edit: Here's a site that looks informative as to RAM, also:
http://computer.howstuffworks.com/ram5.htm
P.S. I'll share whatever links I stumble upon, for those who need more RAM. I have tons of space on my hard drive...it's RAM that I need, but I most def need to read up on it!