So, for my new computer, should I use 64 XP? I have 4 GB of ram. At the same time, I tend to think like mouser, where if the difference is negligible, I don't need it. My computer usage, while extensive, is not really heavy duty in that I use a lot of power. I just do mostly email, file-management, web stuff, some multimedia, pro music applications (very light, not like a studio), and business related software.