I am trying to figure out if I should build a new computer for a user where I work or if it makes more sense to just upgrade what she already has. She has a computer with a 2.6 Pentium D cpu and we are on a tight budget and I was looking at the Pentium G550, but is it any different from the Pentium D? I know the G550 is newer, and thus more advanced architecture, but are we going to see that much of an improvement in performance? They are both the same speed at 2.6GHz and are both dual core. What is the difference and is it worth the upgrade?