How can I free up physical memory on my notebook?
really physical memory is eaten up by running applications on your computer. some of these are probably applications you know you have open, some are also going to be applications you don’t really know are running, for example itunes keeps an application running at all times, as does quicktime. You can prohibit some of these applications from starting when you boot by using msconfig (start–> run–> msconfig), but beware this could have some undesired effects. Memory is pretty cheap also, so you can go ahead and try to add more to your machine. If you visit crucial.com they have an application that will scan your computer, and let you know exactly if you can upgrade and what your options are if so.
