Doom 3 Tweak Guide

[Page 5] In-Game Settings

In this section I provide full descriptions and recommendations for Doom 3's in-game settings, allowing you to achieve a good balance between audio-visual quality and performance. I note the performance impact of each setting, although bear in mind that it is impossible for me to give exact performance impacts - it all depends on your specific hardware combination and your other game and system-wide settings.

To access the in-game settings, start Doom 3 and under the Main Menu you will find the following options, which are explained in detail below:

Click to enlarge


This section has four separate categories for player control options you can change: Movement, Weapons, Attack/Look and Other. The procedure to change any of these is quite simple - left-click on one of the spaces next to the name of the control option and then press the mouse button or key you wish to assign to that control setting. Set these according to your taste, however a handy tip is to assign the right mouse button (Mouse 2) to your Flashlight (under Weapons), to facilitate faster switching back and forward between the flashlight and your weaponry during the game.

See the Advanced Tweaking section for more details of how to use the bind command.

Game Options

Player Name: Enter the name for your character. This is only used in Multiplayer matches. Has no impact on the single player game or performance.

Free Look: When set to Yes, this allows you to use the mouse (by default) to change your character's view direction. If set to No, moving the mouse back and forward will not make your character look up or down, it will make him walk back or forward. Has no performance impact, set to your personal taste.

Invert Mouse: If you are using a mouse in the game to control your player's view, setting this option to Yes means that pushing your mouse forward will make the character look down, and pulling the mouse backward will make him look up. If set to No, the results are the exact opposite. Has no impact on performance, set to your personal taste.

Auto Weapon Reload: If set to Yes, whenever your current weapon has fired its last bullet/charge your character will automatically reload it. Has no impact on performance.

Auto Weapon Switch: Setting this option to Yes means that if your player runs over a higher-powered weapon than the one he is currently holding, he will automatically switch to it.

Show HUD: The HUD is the Heads Up Display - the information around the current player view. This includes health, current weapon ammo, and things such as the video disk and PDA icon. If set to Yes, this information is displayed. If set to No, all such information is removed from the screen. The performance difference is negligible, so it is not recommended that you disable the HUD since it provides valuable information vital to good gameplay.

Show Gun Model: If set to Yes, you will be able to see the weapon you are holding in front of you. If set to No, your weapon will not be displayed on screen, although it will function exactly the same as normal. Setting this to No may improve framerates due to a reduction in what has to be drawn on screen, however not having your gun displayed can cause confusion as to what you are holding, so it is not recommended.

Show Decals: Decals are the marks left on surfaces such as bullet holes and energy scorch marks. Setting this option to No removes all such decals which can reduce realism, but will improve performance, particularly during combat scenes.

Smooth Mouse: This slider controls how smooth your mouse movements will be in the game. The further to the right you move the slider, the less "jumpy" your mouse will feel as your mouse movements are averaged out. Unfortunately for most people, increasing mouse smoothness also results in quite noticeable mouse lag, whereby there will be a slight delay between your mouse movements and how that's translated to what appears on your screen. I recommend you move the slider to the far left to disable mouse smoothing, so that you minimize any mouse lag.

Mouse Sensitivity: This slider determines how sensitive your mouse is in the game. The further to the right the slider, the more sensitive your mouse is to being moved. Adjust this setting until you can turn around rapidly, yet also make small changes in your aim without excessive jumpiness. Has no impact on performance. Note, if your mouse is "lagging" in the game, aside from mouse smoothing (see above), this is primarily due to low framerates. You must adjust your settings to improve your average FPS and you will notice an improvement in mouse lag. Also see the Advanced Tweaking section for more details.

Once you're done changing these settings click 'Apply Changes'.


[Video Settings]

Video Quality: There are two sections under this setting. On the left, there is an option to 'Scan hardware and select optimal video quality', and on the right there are four levels of quality: Low, Medium, High and Ultra. Each is covered below:

Scan Hardware: When this option is chosen, Doom 3 attempts to set the "optimal" settings based on your hardware configuration, automatically selecting your Screen Size and Quality level (See below), as well as a range of other game variables. The rules it follows to do this are heavily influenced on your graphics card model and video memory size. As such, in my experience and based on a lot of reader feedback the auto-detector is almost always wrong. It selects very conservative image quality and resolution settings to maximize your FPS (Frames Per Second), but it is far wiser and more rewarding to change the in-game settings manually (and also do some Advanced Tweaking) to get everything to run smoothly and look great. As such I don't recommend you use this feature, and instead read the remainder of the guide for details on how you can do it yourself. But you knew I was going to say that, right?

Low, Medium, High and Ultra Quality: Below are the major differences between the different quality levels and the associated hardware it is recommended you use to be able to run that quality level smoothly:

Low Quality: This mode is designed for a graphics card with 64MB of Video RAM. It uses compressed textures (textures are the 2D images used on the surfaces of all 3D objects) and light maps, and texture resolution is also limited to 512x512 at most. The reason for this is that large uncompressed textures quickly fill up your Video RAM and cause a lot of swapping into and out of the Video RAM, creating small pauses and freezes. Texture compression and reducing the resolution of textures keeps the Video RAM overhead low, with the down side being some "compression artifacts" (i.e. blurriness, some pixelation and most noticeably a purplish tinge to textures). The game will also use only one sound per event. For example, firing the shotgun has the exact same sound effect every time. This is done to reduce memory usage, as all sounds are preloaded into RAM wherever possible.

Medium Quality: This mode is designed for a graphics card with 128MB of Video RAM. There is still compression used for textures, and light and render maps. Texture sizes are not automatically reduced however, so all textures will appear at their full resolution. There will still be compression artifacts however, but once again this must be done to keep Video RAM demand low. The number of sounds per event also increase, such that there will be some variety for each sound effect at the expense of some system RAM. This mode is the one recommended for most people as it is a good balance of image quality and performance.

High Quality: This mode is designed for a graphics card with 256MB of Video RAM. In this mode there is no texture compression (which greatly increases Video RAM usage), however light maps are compressed still. It is important to note that in this mode, Anisotropic Filtering is automatically enabled and set to 8x, which is quite high. This helps noticeably sharpen textures as they fade into the distance, however it has a pronounced impact on performance. Essentially in High Quality mode texture quality is improved over Medium Quality due to removal of compression and through use of Anisotropic Filtering, but at the cost of a significant performance hit on cards with lower Video RAM and processing power.

Ultra Quality: This mode is the highest possible for Doom 3 and is designed for a graphics card with 512MB (!) of Video RAM. No compression is used for anything, hence while graphics quality is at the best it can possibly be (not including Antialiasing, which you can also enable separately), there is a major performance hit for current systems. Due to the lack of compression loadup times are theoretically reduced, however in exchange for this most systems will notice a lot more freezes and pauses as video information is constantly being swapped into and out of your Video RAM. For the most part the difference between High and Ultra Quality modes is difficult to tell.

Some important things to understand about these settings:

  • Much of the information above has been sourced from this excellent: Official Doom 3 Hardware Guide at [H]ardOCP. I suggest you refer to that article for more details and many, many screenshots which demonstrate the differences.
  • This information is not the last word in what you can and can't do. You can certainly experiment to see how your particular system performs at higher quality levels.
  • In general, the difference between the quality levels is that the higher the quality mode, the clearer the textures will appear, and there will be more variety in the sound effects played. However even at Low Quality the game looks great.
  • You can juggle Screen Size (see below) and Quality settings to achieve good visual quality and performance. For example you can reduce your resolution and increase your quality settings (or vice versa) and see which looks best for you. However just remember that the quality settings are more dependent on your Video RAM, and hence if you only have a 64MB graphics card, attempting to run High or Ultra Quality modes at any resolution may still result in a lot of freezes and pauses regardless.
  • By using certain tweaks you can create your own "Custom" quality settings which fine tune exactly what you want and don't want for optimal performance and image quality. For example, you can enable High Quality mode, then turn off the 8x Anisotropic Filtering separately. You can also reduce texture loading pauses, making some of the higher quality modes more playable. See the Advanced Tweaking section for more details.

  • Screen Size: This setting determines the resolution of the game image. That means how many pixels are displayed on the screen. A resolution of '800x600' means 800 pixels wide by 600 pixels high on your monitor. The higher the resolution, the more pixels shown and the more detailed and clearer the game image, but it takes more graphics card power (and some CPU power) and hence you will see less frames per second. The highest resolution available in this list of resolutions is limited to what your graphics card and monitor are actually capable of rendering (drawing on screen). The resolution has an important impact on your framerate in Doom 3 in conjunction with the Quality settings (see above). If nothing else helps you improve your FPS you will have to reduce the resolution.

    Note: To display Doom 3 in Widescreen mode, or in fact at any other custom resolution, you will need to use the r_mode -1 command and then enter the screen height and width in the r_customheight and r_customwidth settings. E.g. r_customwidth 1280 r_customheight 720 will give the correct aspect ratio for widescreen diplays (16:9). See the Advanced Tweaking section for more details.

    Fullscreen: If set to Yes, this means Doom 3 will run in fullscreen mode. This is recommended, as it provides optimal trouble-free performance. However if you want to run the game in a window instead - and see a performance improvement - select No. This will run Doom 3 in a window with the resolution you specify in the Screen Size setting. Note that if the Screen Size setting is larger than your Windows Desktop resolution, parts of the Doom 3 game window will not be visible. Therefore if you plan on running Doom 3 in windowed mode you should specify a Screen Size of equal to or less than your current Windows Desktop resolution. Note also that running in windowed mode may cause additional problems and instability, due to memory management issues, so bear this in mind if you're troubleshooting.

    Brightness: The brightness slider controls the brightness of the game image. The further right you move the slider, the brighter the image. Brightness values which are too high result in washed out and unrealistic images, especially since Doom 3 is heavily reliant on the element of surprise, suspense and fear all influenced by the game's lighting (or lack thereof). You should also refer to the Advanced Tweaking section for adjustment of Gamma. This setting has no impact on performance.

    [Audio Settings]

    Surround Speakers: If the game detects that you have a surround-sound capable speaker setup, this option can be set to Yes. The game determines your speaker setup based on what you have chosen under the Control Panel>Sound and Audio Devices>Speaker Settings>Advanced section in Windows. Make sure you have the correct speaker setup selected in Windows, as this also affects your audio quality and any audio problems you may experience. If you are unsure of the best speaker settings to precisely match your setup, select 'Desktop Stereo Speakers' in the Control Panel. Selecting Surround Speaker mode can reduce performance slightly due to extra processing requirements, and may also cause some audio glitching on certain systems. See the Troubleshooting Tips section above for more details.

    EAX 4.0 HD: If you have a sound card capable of Environmental Audio (EAX) 4.0 - namely the SoundBlaster Audigy range using the latest drivers - then you can enable this option for a slight performance hit but an improvement in audio quality/positioning.

    Reverse Channels: If set to Yes, the left channel will be outputted to your right speaker channel and vice versa. You should set this to No unless you specifically require this functionality. Has no impact on performance.

    Volume: This slider controls the game volume for both music and sound affects. Adjust according to your tastes. Has no performance impact.

    For more details on how to adjust several other important audio settings in more detail see the Advanced Tweaking section.

    Once you're done with all these settings, click 'Apply Changes' to put them into effect. Note that certain changes require you to close and restart Doom 3 before they come into effect. The next section continues the In-Game setting descriptions.