[CentOS] Diagnosing random hangs

> It is a collection of apps - some of which are X based, some of which
> are not.    The user interface is X, so it is required.  I suppose
> I could get them to run in a VNC server - to remove X and the
> nvidia driver from the equation.
or run the X apps on an external X server.   I've had decent luck using 
Cygwin/X on my Windows machines...   setup putty or another ssh client 
to enable X forwarding, run cygwin's shell, `startx`, let that X term 
open on your desktop and minimize it, then log onto the linux/unix 
machine with putty/crt, then run your X app and it should open on your 
windows desktop.  Works much better than VNC.