Well, those sound a bit high to me. I just started my computer and launched Safari. Activity Monitor shows Used system memory at 747MBs, with Safari using 67MBs, kernel_task is next at 52MBs, then WindowServer and the Dock. Finder wasn't using much at all, so I opened a folder with a batch of graphics files (the window is set to display thumbs in icon view) and selected a file and hit QuickLook, and Finder jumped up to second place, using 55MBs of RAM.
You might restart and then see what you have. You could also launch Console from your Utilities folder and check the Console Messages, see if it looks like anything is struggling with a problem.
Francine
Francine
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