melikia, you have xp64 4GB, I have vista64 8GB, you have Pro Studio, I have Infinite. All these differences can explain the differences in stability and resource usage. Furthermore, I tweaked my Vista for performance. I couldn't care less about all that fancy Aero stuff from Vista so I disabled every graphical aspect from the OS that could affect performance, even remotely. I even have my Vista disconnected from Internet (I write this in my old XP), to make it easier with firewall, anti-virus, spyware and all protection stuff from Vista. The computer is stripped down to pure performance. If I have to exchange stuff with my XP (e.g, downloaded content, upload images), I use a USB disk and physically connect to one or the other computer. I know, it's very primitive, but it works. :-)

How do I operate without mini-preview? When I'm working on a scene, I adjust the quality boost of the atmospheric settings' Light tab to -4, which makes preview renders blazing fast, and I do a lot of preview renders. A lot, constantly. I also use area renders a lot. I switch several times from shaded mode to wireframe mode, depending on the objects I'm using and the kind of positioning I'm doing.