How to Improve Dosbox Performance in Eight Simple Steps

Author: Glenn Scrima

(Please do not copy this guide. However anyone is free to link to this page.)



For those who want to replay old Dos games and relieve old memories Dosbox is a godsend. It comes with a price though. Unlike Dos itself which can run on the simplest of computers Dosbox is an emulated environment and as such requires a lot more horsepower. If you're having trouble don't give up yet though. The good news is that there are a lot of very quick and simple ways to make Dosbox perform better on your machine without losing much if anything in the process. It should be noted that if you have any trouble with these modifications simply go back and change whatever you modified to its original setting. So Without further ado lets begin.


1. Disable the PC Speaker
You may not know it but the pair of speakers on your PC aren't the only ones your system has. Way back in the day computers got by on an internal speaker only. Although you likely can't see this speaker by looking at the outside of the computer it is still there. If you aren't running a game that is real ancient by now its most likely in your best interest to disable this speaker as it will free up a little performance for you. Head over to the Dosbox config file in the folder you are running Dosbox in and right click it and select edit. If you are asked to choose a program to edit the file with choose notepad.

Now with the config file open scroll to the section labeled [speaker]. There should be a line in this section that says "pcspeaker=true". Change that line to "pcspeaker=false". It should look like this.


Save and exit the config file when you are finished.


2. Disable Tandy Sound Support
Tandy is another early integrated sound device that most DOS games won't need since there is usually other better options available through Dosbox. To disable Tandy support again open the Dosbox config file and scroll to the section labeled [speaker]. Under this section there should be a line labeled "tandy=auto". Change this line to "tandy=off". It should look like this.


Save and exit the config file when you are finished.


3. Disable Disney Sound Support
While Disney sound would be a better choice than the last two options it's still likely not your best. Like before head over to the Dosbox config file and open it. Next scroll to the section labeled [speaker]. Under this section look for the line "disney=true" and change it to "disney=false". It should look like this.


Save and exit the config file when you are finished.


4. Disable Joystick Support
If you're not going to use a joystick then this is another shot in the arm for your PC. Again find the Dosbox config file and open it. Scroll to the section labeled [joystick]. Under this section look for the line "joysticktype=auto" and change it to "joystick=none". It should look like this.


Save and exit the config file when you are finished.


5. Disable Midi Support
Now we are moving on to some of the features that are more commonly used in games so that should be kept in mind when changing them. Midi support is used in a lot of DOS games so the decision to disable it could be because that your game in fact doesn't use it at all or you still need the extra performance and can live without it. Either way when experimenting with this setting or any of the settings above remember to play the game after making each change to see how it affects the game. This way you know which change is affecting what if anything at all. As always you can go back to the config file and change it to the original setting. So speaking of the config file find it in your game folder and open it. Once it is open scroll to the section labeled [midi]. Look for the line "mpu401=intelligent". To turn midi off change it to "mpu401=none". The final result should look like this.


Save and exit the config file when you are finished.


6. Disable Sound Blaster or Gravis Ultrasound Support
This is one of the either or situations as you rarely need both. Dosbox by default emulates both the Sound Blaster and Gravis Ultra Sound sound boards. Fortunately you're only usually going to end up using one. The trick here is to figure out which one your currently using in the game. The sound board setting is often chosen during setup or through the main menu of the game. Once you figure out which one you're using then you know which one you aren't and therefore the one to disable. To disable Gravis Ultrasound [gus] support change the line "gus=true" to "gus=false".


To disable Sound Blaster [sblaster] support change the line "sbtype=sb16" to "sbtype=none".


Save and exit the config file when you are finished.


7. Increase the Amount of RAM




Just like any of today's programs DOS games need RAM to run properly. And also like today's programs the amount of RAM you have can affect performance. In Dosbox the default RAM size is 16 MB. Although this is fine for many if not most games some of the more demanding games and ones later in the life of the operating system may benefit from a memory size larger than this. To increase the amount of RAM open the Dosbox config file and scroll to the section titled [dosbox]. In this section look for the line "memsize=16". The number to the right of "memsize" is the amount of RAM available to the game. So "memsize=16" is 16 MB and say "memsize=24" is 24 MB. When increasing the amount of RAM remember that games from the period can "only benefit from so much" as they say so don't go to crazy with the numbers. Trying maybe 24, 32, and maybe even 48 MB should suffice.


8. Enable Frameskip




In a given second your video card will render more than a few dozen frames of images. Although this is necessary to create a sense of motion it can be modified just a bit to ease the burden on your system. The way to do this is by modifying the "frameskip" setting in Dosbox. To do this you need to open the dosbox config file and scroll to the section labeled [render]. Under this section look for the line "frameskip=0". By default Dosbox does not skip frames hence the number "zero" next to "frameskip". However you can increase this number incrementally to see how performance is effected and at what cost to the overall experience of the game. To do this simply change the number next to "frameskip". An example of this might be "frameskip=1" or "frameskip=2". Its a good idea to increase one number at a time beginning at "1".

Well that's it for now. I hope this guide helped you replay your old favorite games in all their original glory. Happy Gaming!

FAQ:
The config file is missing what do I do?
The game won't run on Windows Vista. What should I do?
The game runs sluggish. Is there a way to improve this?
How do I make the game launch in fullscreen mode?
How do I change the amount of RAM available?
How do I mount a hard drive or CD-ROM drive in Dosbox?
How do I change my machine type in Dosbox?
How do I capture a screenshot during gameplay?
I can't download from Abandonia. What should I do?
How do I close or exit Dosbox?

24 comments:

Anonymous said...

My PC ist already 8 years old, so it's more difficult for my to emulate games. This article helped my to improve the gaming speed with bioforge so that it's possible to play it fluently. Thank you.

Glenn Scrima said...

Bioforge is a great game. I'm glad you got it running well since choppy gameplay can take away from the experience. Have fun replaying the game!

Best,
Glenn

Anonymous said...

Hi Glen,
Great help here for dosbox, i've been showing my little boy how warcraft was back in the day. I've got it up and running but is there a way to get the cursor keys to scroll around the screen a bit slower, ditto for clicking on the arrow movement indicators on the edge of the screen. Currently one click or touch of the cursor keys and the screen flys straight to a corner of the environment.

cheers simon

Glenn Scrima said...

Hi, I would try using the decrease and increase cpu cycle special command keys. It may be that your computer is too fast for the game at the default speed. Here's the key commands for each.

CTRL F11 - Decrease CPU Cycles
CTRL F12 - Increase CPU Cycles

I hope he enjoys the game its one of the best!

Best,
Glenn

Anonymous said...

Hi Glenn,

Apologies for the mispell on Glen previously.

Yep that did it ok - thanks.

Any suggestions for something in the config file - there is stuff in there about cycles which I tried but with no result. I wound Warcraft down to 1% using Ctrl F11 to get it working spot on.

Cheers man.
Simon

Glenn Scrima said...

Hi, head back to the config file and scroll to the section labeled [cpu]. In this section you should see the command line "cycles=auto". By default with the newest version of Dosbox the program tries to figure out what this value should be. However with many games like Warcraft on your setup it might work better to enter a value yourself. So to do this you would just need to enter a number like say for example 10000 . So the line would change from "cycles=auto" to "cycles=10000". The lower the number the less cycles the higher the more cycles. This is something you will probably have to play around with to get it perfect but you can always go back and just make sure to save each time so the new value goes into effect.

Have fun with the game!

Best,
Glenn

Anonymous said...

Hi!!!
How can i start to play after i did a double click to dosbix in carmen's folder?

Glenn Scrima said...

Hi after all the files are downloaded and installed and the config file commands are entered the game will launch automatically every time you run Dosbox.

Best,
Glenn

Anonymous said...

Hi Glen, I have to say WOW! I used to play Blood back in the day on the old windows 95 and was annoyed i couldnt play it again once i had upgraded. I play Duke Nukem on the xbox 360 becuase they created the old version downloadable on there. It reminded me of Blood and i really wanted to try find a version that worked on windows vista.

I followed your step by step which worked really well thanks. My only problem is when i play Blood it is really jumpy and i cant play it properly. I checked your FAQ and followed the steps to make it better. After doing so it worked okay for about a minute but then starts being jumpy again. please can you help?

Many Thanks

Richard.

Anonymous said...

Thanks Glenn

I tried outyour suggestions and now everything works flawlessly. I wish they still sold DOS games in local stores like the good old days. With DOSBOX we can now enjoy true games as they are suppose to be written.

Hertyrson

Anonymous said...

Hi Glenn,

Great site, I can't thank you enough for helping to bring back memories playing Syndicate. The only problem I'm having with this game is after the first mission all the briefing writing turns blue, and any missions after that screen the graphics are very distorted. Any ideas what it could be?

Regards,

Paul

Anonymous said...

sorry, i forgot to put in that post that this only happens in full screen mode.

Paul

Glenn Scrima said...

Hi Paul thanks for the compliment. I would try a couple of things that might fix this. One thing I'd try is running the game with an earlier version of Dosbox. Another option would be head to the Dobox config file and find the section labeled [sdl]. In this section is a line output=surface. Try changing it to output=opengl or output=ddraw and see if that helps as well.

Best,
Glenn

Glenn Scrima said...

I agree now eBay is pretty much your best bet although yard sales also have some good deals sometimes.

Best,
Glenn

Joseph said...

umm yeah hey idk what i did but i was playing glory quest 1 and it said it ran out of files or space or something whats that mean and what do i do to fix it?

Glenn Scrima said...

Hi Joeseph is your system low on hard drive space or is this happening within the game itself or dosbox?

Best,
Glenn

Sara said...

When I tried to save my config file, it wouldn't do it and said to make sure the file path was valid. This has never happened before. How can I fix this?

Anonymous said...

ok i got lands of lore working i thought but after the intro movie i select my character and it just stops and a negative image of the char select screen flashes then it goes black and nada..it wont continue to play anymore, I dont know whats causing it so i cant fix.. anyone know how to fix this glitch or have the same prob

Anonymous said...

I followed all the instructions. When I click on the Dosbox program, it only opens the Dosbox, not Psycho.

I noticed that the Psycho files were extracted into a folder called PP. Thinking that might be the problem, I copied them all to the C:\Games\PsychoPinball directory. Still did not work.

I can open the game by clicking "_p_.exe", but it is too slow to play. I tried making all those changes about sound in the comf file, but it did not help.

I am using windows xp on this machine.

Thanks for any help. People can email me at ephraim_fishel@yahoo.com

Mazz said...

how do you get sound to work!?

Anonymous said...

hi Glenn, i have a vista computer, and when i play blood, plasma pak, is says i have only 13 mb of memory, and that i need 24. i have tried going into the conf. file and changing the variables, but nothing seems to work. with only 13 mb's of memory, sometimes the game crashes randomly. can you help me?
-Caleb

Jeremy said...

I was just playing Fragile Allegiance about 5 minutes ago and i got a message saying "video file format wrong" I am trying to play it on a laptop running windows 7. The game runs great no lag or choppiness at all only problem i am having is that message and it crashes out to the Dosbox main screen.Dosbox works flawlessly expect that issue and its probably some thing i am over looking. if you have any idea on how to fix this issue please let me know. thank you.

Griffin said...

So with this tutorial I easily got Warcraft 2 running which I have been trying to do for some time. The problem I have is when I launch the game I cant get it to play in fullscreen. I have tried everything for speeding it up and adjusted the frameskip multiple times but I cant seem to get it to work.

Sean Parker said...

Like Anonymous from March 6, 2010 11:03 PM... I launch Gauntlet, can select 1/2player, then hero, but then it goes black and no response - any Ideas?

Thanks
Sean