Hello! I'm using the GOG verision of Dungeon Keeper 1 that uses DOSBOX. I want to change the resolution to 1920x1080. So, what I did was I changed the notepad file resolution to the following values:
fullresolution=1920x1080
output=OpenGLnb (Also tried OpenGlnb)

Then, in game, I pressed... Insert? Or PageUp? I forget, to zoom out. (It was really freaking blurry.) Then, I pressed "ALT+R" and it made the game look great! So... I think... it worked? But, my problem:

The FPS drops like crazy. Really slows down. I know my rig can handle it. i5 3.2 gHz Nvidia 580 gtx 8gb 1600 RAM etc. etc. etc.

What's wrong?

Go to the .cfg file called dosboxDK, scroll down to cycles, and change it to cycles=max.

ALT+R makes it run at 640X480, which already demands a lot of power from the processor, for emulation reasons, and then you're trying to scale it to 1080p? Yeah, that would take a fair chunk of effort.

I'm not saying it's not doable but good luck getting it running smoothly. You're better off (since it's a 4:3 resolution game) simply scaling it 1280x960, and setting your video card to 'centered' aspect ratio scaling.

If you have an i5 2500k (maybe not?) remember you can safely overclock in BIOS to at least 4 ghz, and this will dramatically improve CPU intensive games such as those running in DOSBOX. Read a guide before touching anything!

I can't find the notepad you guys are talking about. Or the .cfg file. Where is the notepad with file resolution and output, as well as the cfg file. There aren't that many files. So I don't know where they would be.