CPU and Memory usage of XFree86

[Nirmal Govind <nirmalg@psu.edu>]

Hi.. I've noticed that the XFree86 process on my ibook is taking up a 
decent chunk of memory and some CPU and this seems to be slowing down my 
machine a bit .. when I do 'top', XFree86 is a process that's constantly 
at the top of the list.. the process itself, when I do a ps shows up as:

/usr/bin/X11/X -dpi 100 -nolisten tcp

Does anyone know how I can reduce the cpu/memory usage by this process? 
The above process has been started by root apparently.. But I started X 
using the startx command as myself, not root.. is this how it should be?

Thanks,
nirmal