how to change VIDEO DRIVER in Debian Linux
 

During the Installation I choose VESA....but my Video Driver is SIS how to change this?

How to reinstall video driver..

Logout of the desktop then use the CTRL + ALT + F1 keys at the same time once at the console login as root then dpkg-reconfigure xserver-xorg or xserver-xfree86 as the last part depending on which you are using select the Advanced option by using the up/down arrows then Enter key. Follow the dialogs when you get to the part where you chose the driver use the arrow keys again and spacebar to select (if I remember correctly if not Enter key). You may want to put your monitor make/model number into a search engine to find the horizontal and vertical refresh rates as well Debian always sets these too low. Once done use /etc/init.d/kdm restart if using it if gdm put that in there if xdm the same to restart the X server and display manager with the new settings.

thanks i will try that...