Third monitor on laptop is disabled all the time

[jozwik12]

Hey guys,
So while searching my old stuff i found two monitors: LG L192WS and Philips 170S (both have only VGA input). I tried to connect 'em to my laptop so the setup would be like this:
1. Left screen - Philips connected via VGA cable
2. Middle screen - Laptop
3. Right screen - LG connected via HDMI to VGA adapter (Unitec Y-5301)
However, for some reason always one of them is disabled.
My graphic cards are: GT630M and Intel Hd Graphics 4000

 

[Alabalcho]

Laptops have dual-card only, so at any given time only two screens can be active (one driving laptop screen, other driving external screen)