1、打开ubuntu之后的开启页面出现：
所选模式均不匹配可能的模式：
为 CRTC 63 尝试模式
CRTC 63：尝试 800x600@60Hz 模式输出在 1366x768@60Hz (通过 0)
CRTC 63：尝试 2560x1600@60Hz 模式输出在 1366x768@60Hz (通过 0)
CRTC 63：尝试 1920x1440@60Hz 模式输出在 1366x768@60Hz (通过 0)
CRTC 63：尝试 1856x1392@60Hz 模式输出在 1366x768@60Hz (通过 0)
CRTC 63：尝试 1792x1344@60Hz 模式输出在 1366x768@60Hz (通过 0)
CRTC 63：尝试 1920x1200@60Hz 模式输出在 1366x768@60Hz (通过 0)
CRTC 63：尝试 1600x1200@60Hz 模式输出在 1366x768@60Hz (通过 0)
CRTC 63：尝试 1680x1050@60Hz 模式输出在 1366x768@60Hz (通过 0)
解决方法：删除/home/用户名/.config/monitors.xml，重启电脑即可。（.config是隐藏文件夹）
或者ctrl+alt+t，运行终端出来，输入如下的命令， rm ~/.config/monitors.xml
2、ubuntu error found when loading /root/.profile
Upstreaming from https://bugzilla.wikimedia.org/show_bug.cgi?id=46913 :
This used to happen at the start of every Puppet run, because of the line "mesg n" in /root/.profile.
The shell provisioner is actually invoked to fix the problem by changing it to "tty -s && mesg n".
This fixes the problem for every subsequent run. Still, I‘d like to prevent it from appearing even once.
Ubuntu could fix this by adding a check to .profile.
Also see https://bugs.launchpad.net/ubuntu/+source/xen-3.1/+bug/201884
msg n
With:
tty -s && mesg n
In file /root/.profile.
原文：http://www.cnblogs.com/klcf0220/p/4348436.html