Now my desktop extended to 2 monitors: laptop and display connected to laptop via hmdi.
I decided to add the 3rd monitor and connected it via d-sub to laptop.
Windows 7 detectes it in
Control Panel\Appearance and Personalization\Display\Screen Resolution.
I select the 3rd monitor and choose
Extend desktop to this dislplay. Click
Save Changes. But
Multiple displays field revert itselft to
Disconnect this display. And there is nothing on the 3rd monitor.
My laptop video card is
Intel(R) HD Graphics 4000. 3rd monitor model
Lapton model name is
windows 7 ultimate x64
Seemingly it's possible with my video card, but question is how to do it?