Recovery Mode
If SteamOS fails to fully start, or enter the default Big Picture Mode home screen, you may have more serious problems going on. Before continuing below, you will have to boot into recovery mode. To do this, git the ESC key several times as you start your machine. You will reach a GRUB boot menu.
Choose "Advanced options for SteamOS GNU/Linux", which you'll want the first available recovery mode listing near the top. Usually this is the 2nd option after that selection. After some time, the boot process will land you at a root prompt. NOTE: Any commands you enter, should not have the sudo prefix. Please exercise caution.
You will likely need a working network connection. If you need to install libiw30 and wireless-tools, you can get that from the Debian repository. Search for a amd64.deb suffix. Despite this, it is probably just easier to connect you machine to a wired network connection.
# List network devices
ifconfig -a
# Example, call DHCP to get an IP address on eth0 (wired connection)
dhclient eth0
# Enable a wireless connection
# The package 'wireless-tools' is not installed by default
# Load the .deb packages onto a USB drive and continue below
# The USB drive should automount under /media/usb0
dpkg -i /media/usb0/libiw30*_amd64.deb
dpkg -i /media/usb0/wireless-tools*_amd64.deb
ifconfig wlan0 up
iwlist wlan0 scan | less
iwconfig wlan0 essid <SSID> key <WIFI_KEY>
