High Memory Usage in Vista

Vista Ultimate. 1GB RAM. 256MB Nvidia graphics card.
160GB HDD - 80 percent free space. Dual core processor.

I've noticed an unusually high memeory usage in
this Vista Ultimate PC. When you boot up and login
to the PC (joined to a Win2003 domain) the memory
usage is about 36% and stays that way for awhile.
Then, with with no apps open, other than the Sidebar,
and Spy Sweeper (running in the System Tray), within a few hours,
(and not even using the PC), the memory usage goes up to 76% !

Most of it is in dwm.exe, sidebar.exe, svchost.exe, and explorer.exe.
Their memory usage doubles or even triples compared to when the
PC boots up.

The disturbing thing is this PC is not being used. It just sits
there with the screen saver going. So where is all this memory
usage coming from. Is this normal for Vista? Is is preloading apps into
memory?

Hi,

When idle, Vista uses available memory for indexing, defragging, and other
background services. When it detects a user initiating activity, those
processes pause so that the memory is available for whatever task the user
is looking to do. This is normal.

Thank-you.

Windows not doing "anything" is a common misconception. To get a
better idea what Windows is up to, you need to look beyond
applications. Go to Task Manager,then first peek in the processes tab.
For example I just turned on this computer, and lots of stuff is going
on in the background, yet I myself only started up Agent, my news
reader I use to read/post to newsgroups. Still Windows shows 67
processes. Next look in the performance tab, click on the Resource
Monitor, then see the details by clicking on the little down arrows,
like under disk and CPU activity. You'll learn more about what Windows
is doing in real time, even when you didn't ask it to do anything.

Vista does use memory differently than XP and earlier versions of
Windows did. In theory, most of your memory is "used" or in use most
of the time with Windows supposedly being smart enough to release what
it may be using for background operations when something else asks for
it. Unless your PC is running sluggish, don't worry about it.