X probem.

[Lokesh <lokeshnb intotoinc com>]

Hi all,
X will not come back once I log out and try to restart X using command StartX,
I only see a blank screen,
and also when I go out of  X  without logging out, that is 
using  CTRL-ALT-F1 etc.., It wont come
back when I want to get back to X by pressing CTRL-ALT-F7 , and I see a 
blank screen no error message.
What is wrong with this?
I have LG studioWorks Monitor. any cure for this?
Thanks
Lokesh