Physical memory under Windows Task Manager

[memory]

I have a total of 4 gigs of memory installed(2x2). When I go to Windows Task Manager, under the performance tab, it shows I have less than 20 free, 3000 is cached and 4000 total. Is this right? Why is it only showing 20mb free when I have 4 gigs?

I'm not sure if this is in the right place, if not could somebody move it.

 

[peterhuang913]

Because the rest is cached which makes it ready to go.