I've got FC3 running on a Dell Optiplex GX260, P4 2.4GHz, 768MB memory. I know that this should more than suffice for running just about any OS, but since I recently installed FC3, I've noticed that I don't have as much free memory as I should. This is the output of free:

total used free shared buffers cached
Mem: 767264 754404 12860 0 188052 182688
-/+ buffers/cache: 383664 383600
Swap: 1540088 224 1539864

This was taken with Firefox, Evolution, and a Terminal running. I've been trying to investigate and find out what is hogging the memory but when I issue a ps ax | more, there is not a column for %MEM (or something similar) displayed. How can I find out what is taking all the resources? Thanks in advance...

Linux will often show all the memory as being in use, that's just the way it works.

Most of the memory is being used by disk cache, and will be given to any program that needs it.

there is a program in kde called ksysguard that is like the task manager in windows

You can use the "top" command (no quotes) to display the processes that are consuming the most resources.

Also, this article does a great job explaining the basics of Linux Memory Management, and why so much RAM seems to be in use all the time. -- J.W.

There is an easy way to see if a process is hogging mem: fire up top in an xterm and watch the mem% column.
If you want a bit less output press 'i' to filter out all the idle processes.

If you find a culprit of mem-hogging you can kill it with "k" and the PID.

Top is IMHO a must-know, one of those simple and powerful console based apps which makes the difference.