新人~gui遇到了问题

Build Date: 11 January 2016  01:32:44PM
xorg-server 2:1.17.2-1+rpi1 (http://www.debian.org/support)
Current version of pixman: 0.33.3
        Before reporting problems, check http://wiki.x.org
        to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
        (++) from command line, (!!) notice, (II) informational,
        (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.0.log", Time: Fri Feb 26 02:54:50 2016
(==) Using system config directory "/usr/share/X11/xorg.conf.d"
modprobe: FATAL: Module g2d_23 not found.

b+,没有屏幕，网口报废，于是用串口直连。连好后putty-serial开屏。终端正常，但是设置启动进入gui无效。
sudo startx后就会出现最后一行错误代码。