Fullscreen Size Problem When Connected to Another Screen with HDMI on Windows 8.

[Furkanzmc]

Hi.
When I connect my laptop to a bigger screen with HDMI the game screen doesn't cover the whole screen. It sometimes gets bigger than the actual size of the screen, sometimes it's smaller that the actual size. In all cases I use

sf::RenderWindow window(sf::VideoMode(1920, 1080), "Example", sf::Style::Fullscreen);

I'm compiling with MSVC 12 x86.

I shared a picture in the attachment, in that picture there's supposed to be two circle one on top left and one on bottom right, but you only see the top-left one. The window is overflows to the right screen and the primary screen is the laptop's screen.

sf::RenderWindow window(sf::VideoMode(1920, 1080), "Example", sf::Style::Default);

Even with the above code, the window seems much bigger and doesn't fit the 1920x1080 resolution screen.
But when I make the primary screen the one on the right, I have no problem whatsoever.

My laptop monitor's DPI is 140, the device that I'm connecting to via HDMI has 96 DPI. Would that cause a problem?

[eXpl0it3r]

Let me guess: AMD GPU?

Disable scaling for HDMI in Catalyst.

[Furkanzmc]

Sorry I shouldn't have made you guess instead I should have provided the information.
It's NVidia GeForce GTX 950M. I will try doing that.
EDIT: The GPU is not active and I do not open SFML app with GPU, it uses the onboard Intel graphics processor. And although I'm 100% sure, I think Nvidia is not handling the HDMI.

[eXpl0it3r]

Since SFML doesn't support multi-monitor support it will always use the primary screen for fullscreen, which begs the question if your laptop screen is 1920x1080 screen?

[Furkanzmc]

Both the laptop and the external screen is 1920x1080. This seems to be a problem with my computer, I tried it with different computers and didn't reproduce the problem. I tried to look into Nvidia Control Panel but it's missing a lot of the options. I know that it will use the primary screen. In the photo, the laptop is the primary one, when I switch to the external screen the problem doesn't happen.