I am installing Arch Linux on a Thinkpad W530, using the LiveCD.When I boot from the LiveCD, at the Syslinux bootloader screen, my hardware buttons (volume/mute) and Fn-keys work. I am able to control the brightness.But once I boot into the Arch live medium, they stop working. I checked lsmod and have thinkpad_acpi running.Is this just a problem because I am running LiveCD and haven't installed Arch yet?Is there another module that I have to run? Do I need to install Xorg first? I have installed Debian and Ubuntu, and almost everything works out of the box. Including when running their LiveCD. What allows Ubuntu to recognize the Fn-keys? 
Installing Arch Linux on Thinkpad W530
arch linux;drivers;system installation;acpi
I believe the Fn keys are mapped to X86... named keys. Therefore, I'm assuming you have to install the x-server first.  As for the brightness issue, ArchWiki has some relevant information, among which is the possible systemd-backlight problem/workaround:Inverted Brightness (Intel i915 only)Symptoms:after installing xf86-video-intel systemd-backlight.service turns off the backlight during boot  possible solution: mask systemd-backlight.service  switching from X to another VT turns the backlight off  the brightness keys are inverted (i.e. turning up the brightness makes the screen darker)This problem may be solved by adding i915.invert_brightness=1 to the  list of kernel parameters.