When I advise people with their new computer purchases, two of the questions I most often get are:
1) “How much memory (RAM) should I get for Windows XP?”
and
2) “What is the maximum amount of RAM that Windows XP can use?”
Here are the answers:
Question 1: In general, you should aim to purchase the most RAM available that’s at a good price. For most new machines, 1GB-2GB of RAM should be fine for Windows XP. You could always add more if you need to later. Note that if you plan on doing any type of work that is processor intensive, however, such as video editing or heavy multimedia work (e.g. Photoshop) get the maximum amount of 4GB.
Question 2: Even though Windows XP will physically accept 4GB of RAM, by all accounts Windows XP won’t use more than 3GB, however, for a single application. What this all means in plain english is that while XP will allow you to install 4GB of RAM, it will likely only use 3GB max for a single application and use the remaining 1GB for running windows itself. So that being said you should still go ahead and install 4GB (as opposed to only installing 3GB). Also note that even though you may have 4GB of RAM installed, Windows XP stil may only show as having 3GB present, and this is normal behavior for the operating system..
Also note that Windows XP comes in two flavors, a 32-bit version and a 64-bit version. For the 64-bit edition the maximum RAM rules are a little different, but these details don’t generally affect the regular user. If you are not sure what version you are using, the odds are that you are using the 32-bit version.