Low Power Workstation

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Low Power Workstations

  • Motherboard: Via Epia SN18000G
  • Processor: 1.8GHz VIA C7® Processor
  • RAM: 2gb
  • Storage: Compact Flash
  • Case: VoomPC Automotive Mini-ITX Case
  • OS: Ubuntu 8.04 (with gnome)
  • Chipset: VIA CN896 North Bridge
             VIA VT8251 South Bridge
  • Audio: VIA VT1708A High Defination Audio Codec


  • Jumpers for power switch are second two in from the right on the back row, with the rows of jumpers away from you
  • Press F11 during POST to select boot device

To Do


  • Network user profiles


  • Java
  • gedit


  • Boot on PS/2 mouse and USB keyboard
  • Solder power LED on prototype

*Check on:

  • User/global config files for Ekiga to avoid sound device being set to "Default" on first run

Ubuntu 8.10 =

Custom Stuff

  • FUZZY XORG AFTER INSTALL: set driver to 'vesa' OR compile openchrome 902 (901 is the only provided version). Obtain DRM by compiling from git source.
  • BUZZING -> Mute line device for recording.
  • Knowplex and Ekiga don't play nice together unless /etc/asound.conf is added so that dmix works
  • Sample /etc/asound.conf
  pcm.snd_card {
       type hw
       card 0
pcm.dmixer {
       type dmix
       ipc_key 1024
       slave.pcm "snd_card"
       slave {
               period_size 256
               buffer_size 2048
               rate 44100
pcm.dsnooper {
       type dsnoop
       ipc_key 2048
       slave.pcm "snd_card"
       slave {
               period_size 256
buffer_size 2048
               rate 44100
pcm.duplex {
       type asym
       playback.pcm "dmixer"
       capture.pcm "dsnooper"
pcm.!default {
       type plug
       slave.pcm "duplex"
buffer_size 2048
               rate 44100

  • install build-essential for most common stuff needed to build

Compiling a custom kernel

Here's a kernel config file for 2.6.25-7 - use 'make oldconfig' to make it work with newer kernels.

Compile the new kernel by doing:

make-kpkg -initrd --revision=FSepia001 kernel_image modules_image

The revision can be whatever string you want. Use dpkg -i to install the resulting .deb file. You can also build kernel_headers if you wish (it takes a long time though).

I wanted the ALSA release candidate, so I didn't build alsa support in the kernel. Instead I downloaded the release candidate tarball, did

./configure --with-cards=hda-intel --with-card-options=hda-codec-via,hda-generic,hda-power-save
sudo make install

Note that you should be running the new kernel when you do this. Load the new modules by doing

modprobe snd-hda-intel

The module should load correctly on bootup from now on.

Ubuntu Desktop Fails to Start

See: This bug report

The problem is that gnome-keyring-daemon segfaults on startup (apparently related to flash based storage?).


  • edit etc/pam.d/gdm as root
  • remove all references to gnome_keyring
  • save file and restart GDM

Power Saving Tips

Build a kernel with dynticks enabled and use powertop. Some recommendations from powertop:

Suggestion: increase the VM dirty writeback time from 5.00 to 15 seconds with:
 echo 1500 > /proc/sys/vm/dirty_writeback_centisecs

FreeBSD 7.0

Custom Settings

Ports Settings


CFLAGS+= -march=i686 -msse3

Load kernel modules



Disable line-In whine on snd_hda module load



http://lists.freebsd.org/pipermail/freebsd-current/2009-January/002031.html ^^ excellent sound tweaking info (2-18-2009)

Bootup settings




vol 85:85 pcm 75:75 line 0:0 mic 0:0 cd 75:75 rec 75:75 =rec mic

Power Consumption Tuning

Shuttle X27D


-Global desktop icons (xfce kiosk mode? http://www.xfce.org/documentation/4.2/manuals/xfce4-session)


XFCE Settings

XFCE config directory is /etc/xdg

To make xfce-mixer settings static for all users, xfce4-mixer.xml was created by configuring mixer for one user. This file was then placed in the global config directory for XFCE in the following subdirectory: /etc/xdg/xfce4/xfconf/xfce-perchannel-xml

Mixer Settings

Sound card: HDA Intel (ALSA Mixer) Playback Controls:

PCM: 100%
Front: 100%
Mic: 90%
Mic Boost: 60% <-- Without this, the other end of the call reports "quiet and crackly" sound


capture: 40% (with red dot)
digital: 40% (with red dot)


Headphone: checked


Input source: mic

Twinkle Audio Settings

Ringtone, Speaker, and Mic need to be set to "ALSA HDA (ALC662 ANALOG)"

Power Consumption

-1w consumption when off (no peripherals) - connected directly to power outlet --0.56 power factor

-2w consumption when off (kb, mouse, monitor, ethernet connected) - connected directly to power outlet --0.41 power factor

While booting, max power usage reached was 32w for only a moment. Machine consumes 26w whether idle or running numerous applications. While installing packages, consumption was 27w.

Power Consumption With Monitor

-1w consumption when off (kb, mouse, monitor, ethernet connected) and connected to surge protector with switch off.

-3w consumption with power strip on but monitor and computer switched off.

-3w consumption with monitor and power strip on but computer switched off.

-When booting with monitor and computer through kill-a-watt meter, max usage showed 55w during boot. Idle at login screen they are consuming 49w with a power factor of 0.65