For some computer equipped with monitor that resolution is lower than 1280×1024 (or non-standard resolution monitor – widescreen) and installed with Ubuntu 7.10 Desktop Live CD, the boot up screen (USplash) may be blacked or dislocated. The following steps can fix it all :
sudo nano /etc/usplash.conf
Change the xres and yres to 1024 and 768 respectively. Then find out what version of your kernel :
The output in my case is 2.6.22-14-generic (yours may be different if you have updated your kernel). You should issue the following command and reboot the computer after the job done.
sudo update-initramfs -u -k 2.6.22-14-generic