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My laptop has an Intel 3945ABG mini-pci wireless card. Overall it seems to be a pretty good card, but there are some driver issues on Linux (as of 2.6.24). First wpa_supplicant has an annoying habbit of spewing out an error message (ioctl[SIOCSIWAUTH]: Operation not supported) whenever I start up the network interface. It seems to work fine regardless, but the message annoys me. I silenced it by adding the following line to my /etc/conf.d/net:

wpa_supplicant_wlan0="-Dwext 2> /dev/null"

Another problem I had was that the card wasn’t properly powering itself up and down when I restarted the network interface. I took care of that with this little preup script which I also added to /etc/conf.d/net:

preup() {
  if [ ${IFACE} = "wlan0" ]; then
    echo 0 > /sys/bus/pci/drivers/iwl3945/*/rf_kill
    iwconfig wlan0 txpower on
  fi
}

Update: As of 2.6.25 the powerup issue seems to be resolved, but I still see the error message from wpa_supplicant.

Despite its uselessness Capslock takes up some pretty prime realestate on the keyboard. Control, on the other hand, though extremely useful, languishes in the corners. To help fight this injustice I remap Capslock to Control.

For the console on Gentoo I put the following in /usr/share/keymap/i386/include/nocaps.map (I also gzip the file but you don’t have to):

keycode 58 = Control

and add the following to /etc/conf.d/keymaps:

EXTENDED_KEYMAPS="nocaps"

For X I add the following to my ~/.Xmodmap (which I load using xmodmap in my .xinitrc):

remove Lock = Caps_Lock
remove Control = Control_L
keysym Caps_Lock = Control_L
add Control = Control_L

On Windows I use SysInternals excellent Ctrl2cap utility.

I just setup CPU frequency scaling in Gentoo on my Thinkpad T61p (Intel Core 2 Duo). These are the steps I followed:

1. Enable relevant kernel modules/options:
   #
# CPU Frequency scaling
#
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_TABLE=m
CONFIG_CPU_FREQ_DEBUG=y
CONFIG_CPU_FREQ_STAT=m
# CONFIG_CPU_FREQ_STAT_DETAILS is not set
CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=m
CONFIG_CPU_FREQ_GOV_USERSPACE=m
CONFIG_CPU_FREQ_GOV_ONDEMAND=m
CONFIG_CPU_FREQ_GOV_CONSERVATIVE=m

   #
   # CPUFreq processor drivers
   #
   CONFIG_X86_ACPI_CPUFREQ=m
   # CONFIG_X86_POWERNOW_K8 is not set
   # CONFIG_X86_SPEEDSTEP_CENTRINO is not set
   # CONFIG_X86_P4_CLOCKMOD is not set

   

2. Add the appropriate modules to /etc/modules.autoload.d/kernel-2.6 so that they are loaded at boot time:
   # cpu frequency scaling
acpi-cpufreq
cpufreq_ondemand
3. Install cpufrequtils:
   emerge cpufrequtils
4. Set CPU frequency governor in /etc/conf.d/cpufrequtils:
   # /etc/conf.d/cpufrequtils: config file for /etc/init.d/cpufrequtils
# Which governor to use. Must be one of the governors listed in:
# cat /sys/devices/system/cpu/cpu?/cpufreq/scaling_available_governors
#
GOVERNOR="ondemand"
5. Add cpufrequtils to boot runlevel:
   rc-update add cpufrequtils boot
6. Reboot (or start the stuff by hand) and enjoy a more efficient system.