Hi there!

I am having some trouble with this recently. DOSBox games seem not to work if I want fullscreen. It does not matter whether I start directly on fullscreen or I start as windowed mode and then I toggle with Alt-Enter.

What it happens is that it becomes crazy. Main screen gets black, meanwhile Galaxy launcher goes to secondary screen and moves continuously. Then main screen shows the desktop and DOSBox just disappeared.

Both screens are 1080p, but the main one is 144Hz whereas the secondary one is regular 60Hz. The main screen has AMD active sync as well.

For me, fullscreen is a must, and also sharp pixels. Until now, I used to have original resolution and "normal × 3" mode, within the overlay mode. However, Now I am a bit confused.

I didn't do any research, but I surmise it is related to my screen setup. Any ideas?

EDIT:

Some other details:

I use Windows 10 and both CPU and GPU are AMD.

Are you using DOSBox 0.74-2?
What output mode are you using in dosbox.conf?
What fullresolution are you using in dosbox.conf?

I'm using the DOSBox 0.74 distribution GOG includes in almost every game. Should I change this?

Output mode = Overlay

Fullresolution = Original

Thank you for replying ;)

I'd recommend you to:
1. Change output to openglnb or opengl (opengl is with Bilinear Filter).
2. Change fullresolution to 0x0 or desktop, which is your Native Resolution.
3. Set scaler to none.
4. Change aspect to true to keep the original 4:3 aspect ratio.

Thank you very much! I tried just with two games (Alone in the Dark 1 and Theme Hospital) and it worked like a charm!

Could you give some explanation on what happened? Like why Openglnb instead of Overlay? Why no scaler (I guess it relies on the GPU scaling ability)? Etc.

Thanks a lot!

It's possible your video card driver is buggy with overlay mode.

DOSBox by default is setup for CRT displays whereas most people have LCDs nowdays so use 0x0 or desktop.

Set aspect=true since most DOS games are 4:3 and your screen is likely 16:9 or higher.

Yes, please do.

Hey, DiegoPonga, I'm glad you got things working again.

Maybe your problem was just a resolution issue and when you changed it from original to 0x0 or desktop it was resolved.
About the chosen Output, I tried all the options both fullscreen and windowed, and for me, OpenGL was the only
option that worked perfectly and had the best performance.
With the Scaler, you can choose whatever you want as long as you like the result, but if you are using
output=openglnb with aspect=true then things should look sharp and undistorted and there would be no
need for one of these scaler options. personally, I think that some of the scaler options like: hq, super2xsai,
supereagle look horrible.
Also, there is another option called fulldouble (options are true or false) which is Double Buffer,
I think it locks the framerate to 30. It might help in some cases, but I usually set it to false.

Take care.

Which are the differences between 0.74 and 0.74-2? Thank you very much indeed!

I also wanted to ask... Is there any way to set a FPS limiter? I have been messing up with my DOSBox library in GOG and I found some games tend to vary crazily, which can create some flicker and/or some tearing. In some top-down shmups like Stargunner, this was tremendous.

And also, I experienced it takes some 5-10 seconds for my screen to really show the game. This could be due to screen limitations, graphic card limitations or even DOSBox limitations. I'd like to try if using borderless fullscreen windowed mode fixes this. Is there a way to do this using DOSBox?

Oh and by the way: from my 43 DOSBox games in my library, your suggestions worked like a charm! Except for 2 of them. These being Tomb Raider and Wing Commander III. I'll be checking these days different solutions for them, but if you have any of those, would you tell me your .conf specificacions?

EDIT: Ok, for Tomb Raider, just installed the Automated Fix and it worked like a charm.

Thanks for the tips