Basically I get a dell e4500 used, and notice that it had only 2 gigs of ram. Is it possible to add more to it without using readyboost, or is it already at its maximum since it's a all in one machine, like a mac.
Here's an easy solution: go to www.crucial.com and allow the memory upgrade advisor run. The results will provide you with what kind of RAM you're using, as well as what Crucial recommends. If the recommendation shows you options that include more than 2GB, then yes, you can.
If you want a second opinion, you could also go to Dell's website and do the same thing; allow the memory upgrade advisor run.