I installed Xubuntu Hardy about 2 weeks ago. Since then, my machine has consistently shown between 1200mb - 1300mb RAM free. Now today when I turn the computer on, it says I have 461mb free. What happened? I have not installed anything new or changed any configuration since last night...when it showed over 1200mb free. The memory is all being recognized...htop just tells me its all being used...however no process in htop shows up as using more than 3% of memory. Where is all of this RAM going???