A: First, download the new DOSBox enabled Advantage Plus program. You can download the new version here.

The new version has a starter program and DOSBox built in. All you need to do is click Settings from the top right menu of the starter program, and choose "Change DOSBox Window Size". Then slide the bar to the size window you want and click Save.

Old Instructions: Download Program to Automatically Configure DOSBox Window

The recommended method for increasing the size of the window in DOSBox is to download our small program that will update the configuration file for you.
Download conf.zip program.
Unzip the program to your C:\GH folder and click it to run it. Then, select your window size settings from the bottom section. In most cases, you should not need to select anything in the top section, but if your machine opens to a blank screen, that would indicate your video card does not support openGL. In that case we recommend setting the output mode to "Overlay."
Note: You can also use Alt+Enter to stretch the window to full screen size.

Manual Instructions

You can resize the DOSBox window following these instructions:
  1. Open Notepad (in Windows 7, click the bottom left start icon and type NotePad in the program search box).
  2. Click File -> Open.
  3. Navigate to the c-drive, gh folder (or sometimes c:\smartluck\gh folder) and open the file aplus.conf (or dosbox.conf). See the front portion of that file below.
  4. Change the "windowresolution=" setting from 800x600 to 1024x768 or 1280x960. The code below shows that setting with <<<< to the right of it. If you make it any larger than your screen, you will not be able to see the entire window at the same time. (Advanced note: Any other setting that maintains the same proportions as above will work. If you make a setting that doesn't work, Dosbox will ignore it and most likely revert to the 640x480 default setting which is tiny on most monitors.).
  5. Click File -> Save and then open Advantage Plus again, and it will be in the larger size.
------------------ front portion of aplus.conf -----------------------
# This is the configurationfile for DOSBox 0.74. (Please use the latest version of DOSBox)
# Lines starting with a # are commentlines and are ignored by DOSBox.
# They are used to (briefly) document the effect of each option.

[sdl]
#       fullscreen: Start dosbox directly in fullscreen. (Press ALT-Enter to go back)
#       fulldouble: Use double buffering in fullscreen. It can reduce screen flickering, but it can also result in a slow DOSBox.
#   fullresolution: What resolution to use for fullscreen: original or fixed size (e.g. 1024x768).
#                     Using your monitor's native resolution with aspect=true might give the best results.
#                     If you end up with small window on a large screen, try an output different from surface.
# windowresolution: Scale the window to this size IF the output device supports hardware scaling.
#                   Good sizes:  800x600, 1024x768, 1280x960, 1536x1152 (prob too large for most)
#                     (output=surface does not!)
#           output: What video system to use for output.
#                   Possible values: surface, overlay, opengl, openglnb, ddraw.
#         autolock: Mouse will automatically lock, if you click on the screen. (Press CTRL-F10 to unlock)
#      sensitivity: Mouse sensitivity.
#      waitonerror: Wait before closing the console if dosbox has an error.
#         priority: Priority levels for dosbox. Second entry behind the comma is for when dosbox is not focused/minimized.
#                     pause is only valid for the second entry.
#                   Possible values: lowest, lower, normal, higher, highest, pause.
#       mapperfile: File used to load/save the key/event mappings from. Resetmapper only works with the defaul value.
#     usescancodes: Avoid usage of symkeys, might not work on all operating systems.

fullscreen=false
fulldouble=false
fullresolution=original
windowresolution=800x600 <<<< Change this to 1024x768 or 1280x960 
output=opengl
autolock=true
sensitivity=100
waitonerror=true
priority=higher,normal
mapperfile=mapper-0.74.map
usescancodes=true
..
..
----------------------------- End of aplus.conf segment ----------

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