I have a Macbook Pro Unibody (2008? MacBookPro5,1) 2.4GHz Intel Core 2 Duo 2GB RAM I updated my machine to Snow leopard a little while ago too. I did have my internal drive partitioned with bootcamp, but removed this around the time of installing Snow leopard, and now run Virtualbox with XP now on the occasion i need to use Windows. Ive noticed the machine running a bit 'sticky' than normal making photoshop work frustrating. for example, at the moment im running Thunderbird, Chrome, Adium and Photoshop CS4 and clicking on a tool button in PS takes approx 3-4 seconds to get a reaction. I would have thought the machine would be more than powerful enough to be much snappier. Its not even a big PSD file im working on. Is it sometimes worthwhile to do a full wipe and reinstall?