Performance Tweaks

This article relates to performance issues for players. For performance information for mappers, see Performance: Essential Must-Knows

This article relates to the pre-releases Thief's Den and Saint Lucia:

Show FPS

First, you can check how many FPS are achieved by opening the console with Ctrl+Alt+~ (tilde, ^ on German keyboards) and type:

com_showFPS 1

Optimizing the performance

Stop running programs in the background

Programs running in the background might either eat up memory that is needed for Doom3, and thus cause swapping to the hard disk, or they might consume CPU time or other resources. This can cause either general slowdowns or hickups during game play.

Run Doom3 in fullscreen

Running Doom3 in windowed mode might be quite a bit slower than fullscreen mode.

Reduce your resolution!

On older cards, Doom3's render engine is very expensive for every per pixel drawn, and reducing the resolution will help the most. For instance, at 1600x1200 the game needs to draw four times as many pixels as when running 800x600. The result with 800x600 will not look as bad as one might think – but the frame rate improvements might make it much more playable.

Set the ambient shading to "Faster"

Only valid for Saint Lucia:

Inside the settings, change the ambient rendering method to "Faster".

Remove the custom interaction.vfp

(Not valid for Thief's Den demo.)

Rename /darkmod/glprogs/interaction.vfp (e.g., to interaction.bak.vfp) so that it is not used; ambient lighting will not look as good, but you may gain a few frames per second.

The game is very slow!

If you get loading times of 5 minutes or more, less than 10 FPS, or the game even stutters, please try this:

Look into your DoomConfig.cfg inside your saintlucia or thiefsden folder and check that the following settings are like shown below:

 seta image_usePrecompressedTextures "1"
 seta image_useNormalCompression "2"
 seta image_useAllFormats "1"
 seta image_useCompression "1"
 seta image_preload "1"

Image downsizing

As a last resort, you may enable image downsizing: at the console, set image_downSize to 1 and then set a limit with image_downSizeLimit, e.g., "image_downSizeLimit" "256". This reduces texture memory requirements and may completely alleviate hard drive thrashing. There are similar cvars for bump and specular maps as well. Note: This may result in very blurry briefing and menu screens.

Blurry Briefing and Menu Screens

If you get blurry briefing and menu screens then in DoomConfig.cfg make sure you do NOT have image_downSize 0. Instead set it to 1. But see also #Image downsizing

Field of View Decrease

greebo: Beware that this is NOT a recommended tweak, as the player's spyglass will interfere with the FOV 
settings and your custom setting will be reverted as soon as you use the tool.

You can get a performance improvement if you decrease the field of view. By default this is 90 degrees but you might try entering in the console or in your doomconfig.cfg...

g_fov 85

In addition, if you are playing a mission that is too good to miss and reach a very low performance area which is almost unplayable on your machine, you might consider setting the field of view extremely low temporarily to get you through then retore to 90 later...

g_fov 50

Last resort: Upgrade your hardware

Modern games need a lot of computing power, and while you don't need the absolutely newest hardware to play them, upgrading single components of your machine can help tremendously:

• If you got less than 2 GByte main memory, consider upgrading your memory. This really helps to reduce swapping, which introduces quite noticable slowdowns.
• If you got a graphic card from NVidia older than the GF 7x00 series, consider upgrading it.

Upgrading your CPU will be quite complicated and the cost might be so sadly high that you could rather buy a new complete computer. Upgrading the hard disk will usually not help much with gaming, unless you are running out of free space.

See also

See also the FAQ.