I am using Ubuntu 12.04 x64 desktop edition. Previously it works fine, but just now I found that there is a while screen with some black dots when I log off. Then I found that all the grub, tty, and even ubuntu startup screen is not functioning properly. I tried to re-install lightdm, but it does not work.
The linux kernel is 3.2.0-23. I am using an AMD graphic card. The x display is working fine.
The grub. Previously the font was much smaller and the background was purple
The start screen. It should be purple in the background, ubuntu in the middle with five dots below. Now I think the blocks in the middle is "ubuntu"?
all tty are like this. Now I cannot read the words!
Please advise on how to solve the problem. Thank you!