You need to select trident-accell and deselect viacle-accell package when installing for older Via C3 boards.
You can also fix the error by running startx -- -configure and use the newly generated config file to replace the
previous /etc/X11/xorg.conf.
The best way is to install the trident accell package which will also put the xorg.conf needed for your board.

Mon, 2007-04-02 20:07
Joined: 2007-03-28
I have a full version of iMedia I just purchased last week. I can't get x
to load on my Epia Via C3 motherboard. I get "no screens found".
List :
[root@imedia root]# startx
xauth: creating new authority file /root/.serverauth.2252
xauth: creating new authority file /root/.Xauthority
xauth: creating new authority file /root/.Xauthority
X Window System Version 7.1.1
Release Date: 12 May 2006
X Protocol Version 11, Revision 0, Release 7.1.1
Build Operating System: Linux 2.4.33-imedia i686
Current Operating System: Linux imedia.your.domain 2.6.18-imedia-i586 #1 PREEMPT Fri Dec 15 12:39:00 EET 2006 i686
Build Date: 27 July 2006
Before reporting problems, check http://wiki.x.org
to make sure that you have the latest version.
Module Loader present
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: Sat Mar 31 16:51:59 2007
(==) Using config file: "/etc/X11/xorg.conf"
(EE) No devices detected.
Fatal server error:
no screens found
XIO: fatal IO error 104 (Connection reset by peer) on X server ":0.0"
after 0 requests (0 known processed) with 0 events remaining.
[root@imedia root]#