i installed mandriva2007 successfully and was asked for rebooting .but after all the initializations the screen goes blank and nothing comes up.what could be the problem?

Do check the BIOS if your first boot device is the hard drive

If you get a blank screen on the first reboot it is likely due to a mismatch of the video driver. No display and therefore no communication, although Mandriva can be waiting for you in the memory.

In most cases pressing ctrl+alt+backspace can drop you back to the terminal mode with which you can repair the xorg.

In terminal you can run "xorgconfig" to reconfigure the Xwindows. If you know your video driver type it may be quicker just edit the configuration file /etc/X11/xorg.conf.

Try vesa as the video driver if you are not sure of the video card and make sure the scanning frequencies of your monitor match the xorg setting of HoriSync and VertRefresh rates. The latter is a common mismatch if you use a LCD monitor whereas Mandriva installer assumes a CRT monitor.

If you get the terminal mode then your installation is good. The rest is just fine tuning.

i changed the driver to vesa and now it is working thanx a lot but still mine is actually sis 300 why does it not work with that

Unless you source the video driver and install yourself those available in Linux are generic. The vesa is the common standard on video display. It is likely that driver like "sis" could work in your case too.

Video drivers are proprietary items and if the vendors are not supplying them to Linux then what can Linux do?