Black X in the middle of the screen

[Artur]

Hello to all !

I've got one question - about two days ago I installed Ubuntu on my
laptop (Fujitsu Siemens Lifebook C1020). The problem is, that almost
everything runs fantastic - almost because in the middle of the screen
I've got black X that I can't get rid of - it's like the state when X-
window has just loaded, but the theme of cursor hasn't.
I also tried on this computer SuSE 9.1, Slackware 10 and Fedora Core 2 -
and these distros ran fine, so using linux on laptop is not the problem.
Can anyone help me ?

Thanks,
Artur