Well I have a powerbook g4 and upgraded the RAM to 1.25Gb Anyways, my computer hasnt rebooted yet. I know the simple fix is simply reboot, however I rather not... Anyways, here is the issue, I have 624mb of ram that Activity monitor lables as "Inactive." Is there anyway to free the memory other than rebooting? More importantly why is it inactive? I already closed down ALL the programs that I possibly can (Finder simply cant!) and looked at the Activity Monitor and no programs that are running is using that much memory. Why is it inactive anyways?