The classic Doom games has been ported and re-release to various systems throughout its lifetime, though the Steam re-release of the classic Doom games unfortunately has some issues thanks to using an outdated build of DOSBox with the incorrect settings, and missing a lot of core configuration files need to change settings of these games. Although you could play these games on a source port like GZDoom or PrBoom+, and while there's nothing with that, but at the risk of sounding like a purist, the whole purpose of this guide is being to play Doom on DOSBox as provided on Steam along with some tweaks and changes so it runs smoothly.

In the following steps I'll use The Ultimate Doom as an example but the general idea should work for the other classic Doom games on Steam. For those that purchased any of the classic Doom games on Steam, there is a major problem with settings that was packaged with Doom — especially for Windows 8 or 8.1 users — and the version of DOSBox included is sorely outdated. It's sad that the MS-DOS version of these games are being shipped in this way with DOSBox, but I guess that's what I'm here for. The version of DOSBox that is included with the Doom games is v0.72 or v0.71. The version you need is, as of writing this guide, v0.74-3. The latest official version of DOSBox can be found at its homepage at the link below where you can download and install the program.

• Official website[www.dosbox.com]

Once you have downloaded and installed the latest DOSBox, the files you need are "DOSBox.exe", "SDL.dll", and "SDL_net.dll", which can be commonly found under C:\Program Files\DOSBox-0.74 if you're on a 32-bit version of Windows and using the default install location; for 64-bit Windows users, DOSBox's installation should be found under Program Files (x86) instead. Alternatively you can use something like 7zip to extract the files from DOSBox's installer executable and extract the necessary files without having to use the installation set-up. Take those three files and replace the outdated files provided with your Steam copy of Doom with the newer ones. You can quickly find your game's installation folder by right-clicking the game on your Steam Library and clicking "Browse Local Files" from the drop-down menu.



The Ultimate Doom, Doom II: Hell on Earth, and Final Doom DOSBox location:

Master Levels for Doom II DOSBox location:

The next thing you should do update the *.conf files bundled with your game. The "dosbox-v0.74-3.conf" file with the updated default settings can found under <Username>\Local Settings\Application Data\DOSBox\ for Windows XP or C:\Users\<Username>\AppData\Local\DOSBox for Windows Vista or later. The quickest way to access your DOSBox's *conf file by going into your Start Menu → DOSBox <version> → Options, then run the DOSBox Options shortcut. Alternatively, you can quickly access your AppData's folder by pressing Windows Key+R to bring up the Run command, then type in "%appdata%" or "%localappdata%" in the dialogue box and press Enter. If one doesn't already exist in the locations I mentioned, run the latest DOSBox once and close it so it generates a fresh one for you. Open the file "dosbox-<version number>.conf" with a text editor if you used the alternative method (e.g. Notepad, Notepad++), copy all of its settings EXCEPT for the [autoexec] section since the that section runs commands in the DOS interface for you, then paste these settings into "ultimate.conf" (which uses the original arrow key configuration), "ultimatem.conf" (which uses a modern mouse and keyboard configuration), and "dosbox.conf" (which DOSBox normally reads from; optional) while leaving the [autoexec] section alone and the commands in that section as is. I highly suggest Notepad++ for this since it can let you modify multiple files at once in a single window.

Before (left) and After (right):

Now that you have an updated version of DOSBox with proper settings to run Doom, it should work on your computer just fine without using the not-so-helpful method of changing settings that didn't cause problems with playing Doom or setting DOSBox's compatibility mode Windows 95 since that didn't work for me and others using Windows 8. Now here is a basic rundown of some of DOSBox's settings. If you need help with understanding the settings, refer to the DOSBox Wiki's dosbox.conf article for detailed explanations for all of its settings.

• http://www.dosbox.com/wiki/Dosbox.conf#Sections

fullscreen=
Enable or disable full screen when launching DOSBox. It's normally set to false but the *bat files forces full screen anyway. I'll show you show you can change that later on in this guide.

fulldouble=
This is one of the sources of the problems for Windows 8/8.1 users with Doom. This enables or disables double buffering when playing in full screen. It is advised keep this at false since it has been known to cause problems and slow down DOSBox. In the case of Doom, the start-up sequence gets slowed down, regardless of the CPU cycle settings, and DOSBox freezes when it gets to the title screen with DirectDraw or Surface rendering in full screen with double buffering. Therefore, keep this setting off.

fullresolution=
This changes the resolution size when running in full screen. By default with the outdated version it was set to 800x600 instead of its default setting of original. You can set this to any resolution supported by your monitor or TV, but if want to the game to run in your native resolution in full screen mode, it's recommended to set this to either 0x0 or desktop.

windowresolution=
Same as above but for windowed mode. original works fine but you can set this to any predefined resolution (e.g. 640x480) supported by your monitor or TV if you wish.

output=
This changes the video output method of DOSBox. By default in the outdated version it is set to ddraw where it uses DirectDraw to render the game, or surface on v0.74. As stated in "fulldouble" above, DO NOT USE ddraw OR surface RENDERING WITH DOUBLE BUFFERING ENABLED OR EXPECT ISSUES IF YOU'RE ON WINDOWS 8/8.1. Personally, opengl and openglnb seems to work the best on DOSBox for non-ATI video cards, otherwise use overlay if that works better for you. More information about the output settings can be found here at VOGONS.

• http://www.vogons.org/viewtopic.php?=&p=102291

machine=
This tells DOSBox what IBM PC machine (mainly in terms of graphics) to emulate. The older version used vga as its default setting, but since v0.73, the new default is svga_s3. svga_s3 is recommended since not only is this is a higher end system, it is also mostly backwards compatible with games that uses older VGA graphics but not anything like the Hercules, Tandy, and or PCjr machines.

frameskip=
This tells DOSBox how many frames it should skip before drawing one. Generally should be left alone at 0.

aspect=
Aspect-ratio correction. This is only works non-square pixel display modes like VGA Mode 13h, which ran in a 320x200 resolution that was commonplace for many DOS games, such as Doom. It is recommended that this setting is set to true if you wish to play in the intended 4:3 aspect-ratio.

scaler=
Changes the scaling method for low resolution mode that DOSBox uses if the output setting is using something other than surface. normal2x or normal3x works fine, but other settings like hq2x seem to work better when ddraw rendering but it can may also make the game load a bit longer than usual with official builds of DOSBox. This also affects the screen size when the "windowresolution" setting is to original (e.g. original windowed resolution + normal2x + aspect-ratio correction enabled = 640x480). However this setting may not work well if "fullresolution" is set to original and the "scaler" is set to none.

If configurating DOSBox and manually setting up the configuration files for the Doom games so it'll run properly in DOSBox is something you're not into doing but still want to use DOSBox to play these games, I've prepared some files to make things relatively easier to install the fixes and restore missing files need to set these games up, along with some alternative DOSBox configuration files based off the GOG release that gives you options either to launch the games or configuration tool.

• Download[1drv.ms]

Here are some other settings and things you can mess around with.

NOTE: This only works on Windows operating systems. If you don't like seeing the console window that shows up when running DOSBox, open the "doom2.bat" and "doom2 + mouse.bat" files with a text editor then replace this into the *bat files.

doom2.bat

doom2 + mouse.bat

The "-noconsole" command will not display the console window that opens when running DOSBox and will instead put the debug information in stdout.txt. The "-fullscreen" part of this command was also the reason why DOSBox kept running in full screen despite disabling full screen start up in the *conf files. You can delete that part so it'll start in windowed mode if the "fullscreen" in the *conf files is set to false.

There is also a way to have the Windows command prompt window close itself when launching Doom by altering the commands in the *bat file, but since the Steam release of Doom wasn't packaged in a way where the game starts from DOSBox's own executable rather than a *bat file, Steam won't track your playtime if the command prompt window is closed.

A guide by rogeilor has been made for playing Doom with keyboard and mouse without vertical mouse movement interfering with player movement. This also works with the other classic Doom games as well as Heretic and Hexen since they use the same engine as Doom. novert is also included in the pre-made fixes above.
http://steamcommunity.com/sharedfiles/filedetails/?id=134328758

I would like to the DOSBox team for this neat little DOS emulator that allows us to play many PC classics on today's modern computers, VOGONS forums for the info about DOSBox's video output settings, rogeilor and Alaan_ for their guides on tweaking classic Doom on DOS and allowing me to share them here, and of course those that took their time to read this guide I put together. If this guide helped those looking to play Doom on DOSBox with newer Windows systems, maybe I'll make a guide on how to up the MIDI playback quality by using soundfonts, play Doom on ZDoom with near-vanilla Doom settings, play PlayStation Doom on your PC with the PlayStation Doom Total Conversion, and play Batman Doom on ZDoom.