Ubuntu: Install with video drivers disabled

When I tried to install Ubuntu 12.04 on my PC, it halted with 4/5 dots under Ubuntu. It's stuck at that point and no progress. Sometimes you may see some distorted image or white screen. All these problems are due to incompatible video drivers.

To get pass behind this screen and boot into the system, hold down SHIFT button while booting from CD/USB and press F6. Now select "nomodeset" option to prevent video drivers from loading.

Now you can install Ubuntu successfully. But you may face the problem again while booting (after installation). Then boot in "Recovery Mode" and install graphics drivers from GRUB menu or command line.