You will need the livebox for the 2rd line as you will need to plug in the phone adaptor that came with your livebox as that is where you plug in your spare phone. If you don't want to use the 2rd lin ...
Well, First of all, You have to make sure the options of energy management are disabled for your ethernet card.
Windows + Break > Device Manager> Network Adapters> ethernet card> properti ...
It could be either . If you were having similar problems with the old one it does point to the graphics card being the problem I reckon. Try swapping monitors if thats possible or putting the tft onto ...