Automatically switch to big monitor on login

Here's the deal: when I login into my KDE environment, I want system to check if my large monitor is connected and to switch to this monitor if it's found. The laptop screen I want to turn OFF (the system heats up enough with only one screen used; besides, I couldn't find any real use for 2nd monitor, probably because of lack of imagination).

After playing a bit with systemd, I gave up and simply added a script to KDE's autostart.

Here's some information one need to get before you write such a script for your configuration:

Dual-monitor configuration

Just couple of xrandr commands (after struggling with KScreen-like GUI tools without results).

1. Choose big screen:

xrandr --output VGA-0 --mode 1920x1080 --output LVDS --off

2. Use both screens (notebook is to the left of its big brother):

xrandr --output VGA-0 --mode 1920x1080 --left-of LVDS --primary --output LVDS --mode 1366x768

Notes:
- Notebook's screen is LVDS and big monitor is VGA-0; you may check your outputs by calling "xrandr" without parameters
- Resolutions are 1920x1080 and 1366x768 respectively

Don't let your USB mouse die!

Annoying thing: when you try to use USB mouse, it goes to "sleep" mode after only few seconds of inactivity (mouse inactivity), meaning there is no more red light at it's bottom and it doesn't respond to movements. You should click buttons to have it awaken.

The issue is related to powersaving, and it can be saved with using the following command:

for i in /sys/bus/usb/devices/*/power/control; do echo on > $i; done