Hi, everyone!

I keep reading a lot of threads asking the same thing over and over. Just for instance, we have replied two of them today.

It seems some people are having problems running DOSBox fullscreen, even if DOSBox works just fine on a window. In some cases they get a blank screen or the screen is too big (or too small) o is uncentered or out of synchronization.

Most of the times, the solution is QUITE SIMPLE. Some monitors/LCDs/TFTs etc may be expecting some FIXED RESOLUTION for running in fullscreen and many people isn't aware (or doesn't care) to know that DOSBox doesn't use a FIXED FULLSCREEN resolution by default. Keep in mind that TFTs come with a "native resolution" as preferred one and while they could do other resolutions, it won't be the same because they don't work as common CRTs. They are less permissive and things tend to look worse on other resolutions than native one. For instance, my TFT has a native resolution of 1280x1024. All other common resolutions work too, but they look slightly blurrier.

To solve this problem...

Edit dosbox.conf (inside your DOSBox folder) using a text editor (like Notepad, if you are using Windows). And look for the two parameters (must be editted together):

fullfixed=false
fullresolution=1024x768

These are the default parameters for DOSBox, i.e, not use a FIXED resolution when going fullscreen. We want to specify one, so we must change the values to...

fullfixed=true
fullresolution=1280x1024

The example above will make DOSBox always switch to 1280X1024 resolution when running FULLSCREEN.

Have fun!