Have an NVS 4200M card in your laptop? Here’s how to use the laptop screen as a 3rd monitor
Last year I was issued a new laptop with an nVidia NVS 4200M video card. I was able to to hook two monitors up to it through a docking station and use the laptop monitor itself, for a total of 3 monitors. Good times!
Recently, however, I had to get my machine reset so we could downgrade my Windows 7 Enterprise to Windows 7 Pro due to licensing issues. When I got it back, I could only get two monitors to work. Whenever I’d try to enable a 3rd, one of the other two would get disabled. Going into the nVidia control panel, it told me that my GPU only supported two displays. I knew this was false since it had previously been working! Thinking maybe it was just a driver issue, I updated to the latest nVidia drivers to the card, but to no avail.
After poking around some more I found the answer. There’s a setting in the BIOS that had apparently been reset when my machine was reconfigured. I just had to flip the flag back on to enable nVidia Optimus support, and suddenly I was able to use my laptop screen as a 3rd display again!
Since I know we tend to buy the same sorts of machines all at once, I figure there might be other people out there who have the same machine but haven’t been able to get three displays enabled. Hopefully this helps!