Deus Ex Tweak Guide
Posted: July 2, 2000
Written by: Keith "Farrel" McClellan


Deus Ex - the game that everyone is raving about. They are raving about the graphics, the gameplay, and the storyline. The only problem is that people are also raving about how badly it runs on their system. This game is a resource hog, just like any other Unreal engine game. Maybe you thought that they would have fixed this by now - but they haven't. However, that doesn't mean there isn't anything you can do about it - as a matter of fact, there is plenty you can do about it, and I plan on educating you on it right here.


This game has a very interesting, but very Unreal-like, setup program that allows you to choose which of the extra components you want to have installed to the hard disk. First and foremost, to improve performance, I would recommend installing the Game Content to the hard drive - this will not only save on level load time, but it should also cut into some of the lag it is possible to run into in the game. For even more performance, loading the game maps to the hard drive should improve load times and system speed as well. Installing speech to the hard drive might speed up the system slightly, but it isn't nearly as significant as the other two installation options - only install that if you've got the space to spare.


As with every game, Deus Ex performs best under the most recent stable driver version available from the manufacturer of your gaming hardware. The two most important pieces of hardware to have new drivers for are the video card and the sound card. The video card drivers obviously speed up the 3D rendering, but the sound card drivers frequently take some of the strain off of the processor - freeing it up for more important things such as AI calculations. At the same time, DirectX 7.0a is included along with the game - if you have an earlier version of DirectX installed, it is advisable to install these drivers as well if you plan on running in DirectX mode (which is preferred unless you have a 3dfx video card.

Rendering Device

Before you actually get to go into the game and start, you are given the choice of rendering devices. For the most part, there are three different options most people will have to choose from - DirectX, OpenGL, and Glide. If you have glide available to you, use it - it is much faster than the other two options. However, if you aren't running a Glide-compatible video card, it would be advisable for you to choose DirectX over OpenGL. DirectX is much faster and I think you will find it is less buggy than the OpenGL implementation in Deus Ex. Would someone go over to Epic and whoop up on them for being lazy asses and not getting any of their non-proprietary rendering engines up to speed? I'd appreciate it.

Display Settings

Seeing that this is an Unreal engine-based game, we could skip straight to the preferences applet and totally forego the in-game settings bit, but seeing as I am a bit soft on anything that makes my life even the littlest bit easier, I'm going to jump into these in-game settings like a monkey jumps into a pile of bananas (excuse the bad pun).

The display settings are the first set of settings I am going to speak about. The first in a series of available settings is the screen resolution. You can pick from the standard resolutions of 640x480, 800x600, etc, as well as some not-quite-so-standard settings. Choose the one you are most comfortable with - a higher resolution will result in better graphics while a lower resolution will result in better game performance. The next setting, color depth, gives you the choice of 16 and 32 bit color. 32-bit color is always nice, but 16-bit color still looks pretty good and performance is generally higher when using it.

The next two settings, World Texture Detail and Object Texture Detail, have to do with the quality of the textures used within the game. There are three possible settings with each of these - high, medium, and low. High will use the best quality textures available and low will use the worst quality textures available. Medium is something of a compromise between the two, however I wasn't able to notice much of a difference between the medium and the low quality textures (particularly at lower resolutions).

The last two settings are on/off settings - Detail Textures and Decals. Detail textures has a profound impact on how well the game looks so if you have any choice in the matter, leave it enabled. However, disabling decals can make several parts of the game significantly faster and there isn't much lost from the game with them disabled.

Sound Settings

The other type of setting I recommend editing from within the game would have to be sound. The first of the settings that need to be looked at is the effects channels setting. The maximum setting for this is 16. Lowering this setting will free up processor time for other things, but if you are planning on enabling 3D Sound support you might as well leave this at the maximum allowed setting.

Sample rate is another important setting that can significantly speed up the system in some cases. If you aren't much of an audiophile, or your computer speakers aren't very good, you can probably get away with dropping the sample rate down from 44 KHz to 22 KHz - only drop the setting down to 11 KHz if you are seriously struggling for CPU cycles though. Quality is another thing you can change within the sound preferences - 16 bit is pretty much the standard, but, once again, if you are struggling for CPU cycles you might consider dropping it down to 8 bit.

Sound Settings (cont.)

The only other two settings have to do with 3D sound implementations. The first one, Dolby Surround, should only be used if you are using a Dolby compatible 5.1 speaker system with a built in decoder. The other setting, which enables 3D hardware, should be used only if you have a main brand sound card like Aureal or Soundblaster. Otherwise leave that setting alone as well.

Getting to the Preferences Menu

You have to do a little game hacking to get to the console, and hence the preferences menu, in Deus Ex. First, browse to your Deus Ex directory and open the system folder. Inside there, look for and open up the user.ini file (doesn't this sound a bit like tweaking UT?). Look for a line under the key bindings that says Tilde= and after the equals, add the word talk. Save the file and then load up a game of Deus Ex. Press the tilde [~] key, delete any text that pops up in the command line and then type in the word preferences (as it was in UT). This will force the game back into windowed mode and load up the preferences menu. It's all smooth sailing from here.

Advanced Options

Seeing that a bunch of the tweaks available in the advanced options (also known as preferences) menu are also available in game, I will avoid those and just tell you about all of the sweet ones that you can't get elsewhere.

- Advanced - Under the advanced section of the Advanced/Preferences Menu there is a setting called CacheSizeMegs (under the Game Engine Settings subheading). The standard setting for this is 0 in Deus Ex - However, seeing that I trust the original programmers a bit more than the guys over at Ion Storm, I'm going to go out on a limb and recommend that you set this up to 4 (the default setting for Unreal and Unreal Tournament. It'll help - trust me.

- Audio - Under audio, I would recommend enabling CD Audio if it isn't already selected - this should make the background music sound better and will use less computer resources to boot. I would also recommend enabling lowsoundquality to increase speed, as well as disabling 'UseReverb,' which removes some 3D sound effects.

- Under display you can enable a feature called CurvedSurfaces, which enables, well, curved surfaces. If you've got a 3dfx card and a decent processor, you can try this out for some visual quality improvement, but it is unlikely to work very well on D3D. As a matter of fact, it did not run well at all in D3D in our tests, so you would probably be better with it disabled in that case.

Advanced Options Continued...

- Rendering - there are four main subsections here that should be tweaked - you should only tweak the one that you are currently using for Deus Ex.

o 3dfx Glide Support - Make sure that the DisableVsync setting is set to true and that your refresh rate is set to how you like it. The default, 60 Hz, is way too low - you should have it set to at least 75 if your monitor supports it at that resolution.
o Direct3D Support - You should pretty much have everything enabled under Direct3D rendering if you aren't having any speed problems. The notable exceptions to this would be Use3dfx and UseVsync. You should only have Use3dfx set to true if you are running a Voodoo3 in D3D mode and you should never have UseVsync enabled unless you are having large tearing issues. If you are having speed problems at your chosen resolution, you should disable the following features in order: UseTrilinear, DetailTextures, Volumetric Lighting, ShinySurfaces, HighDetailActors. If that still doesn't help, you can also try disabling some of the other settings - just make sure you take note of which.
o OpenGL Support - I wouldn't recommend using OpenGL for your renderer in Deus Ex, but if you choose to do so anyway I would recommend disabling VolumetricLighting, ShinySurfaces, HighDetailActors, DetailTextures, and Coronas to start out. If you find that the speed of the game is acceptable, start enabling one at a time until the game gets too 'choppy' to play. Hopefully, however, this will not be an issue if you are running on a newer card such as a GeForce 2 GTS.
o Software Rendering - If you are one of the unlucky few that must use the software renderer (which I didn't even mention earlier in the guide because it is so infrequently used nowadays), you probably aren't going for much in the way of visual quality. To improve the speed of the software renderer, make sure that the game is set to 32 bit color and then go ahead and enable LowResTextureSmooth and FastTranslucency. Everything else should be disabled. If you find that the game is more than fast enough, go in and enable some other features - perhaps moving up to HighResTextureSmooth and VolumetricLighting.

Game Updates

If you have tried everything else and you are still having trouble with the game, you could check out the game's website to see if there is a game patch or workaround available for your problem. Game patches, however, have the slight chance of invalidating your saved games - so you will want to check on that beforehand - it can be very annoying to install a patch and then realize you've got to start the entire game over again.


Well, there you have it - the Deus Ex tweak guide. Hopefully you will find this guide useful in your quest to get Deus Ex running the way it was envisioned. It is quite curious that the people over at Ion Storm chose the UT engine over some of the other available engines at the time that are better suited for a single player game (Deus Ex has no multiplayer functions at this time whatsoever). Perhaps they will add such features at a later date (I seriously doubt it though). As always, feel free to email me with any comments or questions you have about this guide.

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