It also makes your computer weigh more. Unless you have two 2gig sticks instead of three 1gig sticks, then it will make it weigh less.

As a general rule, more RAM is better unless your system or OS can't support it fully, or your programs are not using what you have now.
 

Nakkiel

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Mar 14, 2011
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In terms of internet applications, the extra gig will give space on the ram for the browser to use if you are close to using 3 gig. Fairly useful for web browsing while playing a game that uses a lot of RAM.

If you are actually asking if its worth upgrading to 64-bit to make full use of 4 gig of RAM instead of being capped then you are probably better off with 32-bit since 64-bit uses more memory and will run 32-bit programs slightly slower, unless of course you are fully using that 3 gig and really need that little extra. If your currently doing a system install and plan to add more RAM later then definitely go with 64-bit so you don't need to reinstall later.