Killing Floor Client Config Diffs

This page collects practical KillingFloor.ini and User.ini edits for KF1 clients. The focus is on sound options, hitch reduction, cache and video memory values, mouse smoothing, weapon pickup behavior, and blur.

Before editing, back up your config files. If the result is worse, restore from backup or regenerate defaults from the game.

Backup Files

LazyKFWiki linked default config backups:

Typical config folder:

KillingFloor\System

KillingFloor.ini: Better 3D Sound

In [ALAudio.ALAudioSubsystem], the original note enables EAX and 3D sound, disables default-driver fallback, and raises channel count. The important values are:

UseEAX=True
Use3DSound=True
UseDefaultDriver=False
CompatibilityMode=False
MaxEAXVersion=255
ReverseStereo=False
Channels=64

Channels=64 can noticeably change the sound mix. If audio becomes strange, lower the value or restore the original section.

KillingFloor.ini: FPS And Hitch Reduction

The page describes two precache profiles. The stable profile loads longer but aims for fewer in-game hitches:

UsePrecaching=True
bNeverPrecache=True
UsePreCache=False

The quicker-loading profile may start faster:

UsePrecaching=False
bNeverPrecache=True
UsePreCache=True

Extra stability and memory-related values:

[Engine.GameEngine]
CacheSizeMegs=256

[Engine.Engine]
DetectedVideoMemory=2048
NVidiaGPU=True

[D3D9Drv.D3D9RenderDevice]
CheckForOverflow=True
AvoidHitches=True

The original warning is important: values above CacheSizeMegs=256 can eventually crash the game. DetectedVideoMemory should match your GPU VRAM instead of being copied blindly.

Mouse Smoothing: KillingFloor.ini

Mouse input in KF1 can feel delayed because of frame smoothing and old renderer behavior. In client sections, keep the desired frame rate low:

[SDLDrv.SDLClient]
[WinDrv.WindowsClient]
MinDesiredFrameRate=1.000000

For the renderer you actually use, disable reduce-mouse-lag handling:

[D3D9Drv.D3D9RenderDevice]
ReduceMouseLag=False

Other possible renderer sections include D3DDrv, OpenGLDrv, and PixoDrv.

User.ini: Mouse Smoothing

In [Engine.Input], the note recommends a lower axis speed:

MouseX=Count bXAxis | Axis aMouseX Speed=1.0
MouseY=Count bYAxis | Axis aMouseY Speed=1.0

In [Engine.PlayerInput], disable smoothing and acceleration:

MouseSmoothingMode=0
MouseSmoothingStrength=0.000000
MouseSamplingTime=0.001000
MouseAccelThreshold=-1
MouseSensitivity=0.500000

MouseAccelThreshold may reset when the in-game menu is opened, so check the file again after changing menu settings.

Menu mouse sensitivity can be set in controller sections:

[XInterface.GUIController]
[GUI2K4.UT2K4GUIController]
[KFGui.KFGUIController]
MenuMouseSens=0.400000

User.ini: Disable Auto-Switch On Pickup

To stop the game from switching to a newly picked weapon:

[Engine.PlayerController]
bNeverSwitchOnPickup=True

User.ini: Remove Pawn Blur

To disable the human pawn blur effect:

[KFmod.KFHumanPawn]
bUseBlurEffect=False

Test Checklist

Start a solo game after each group of edits.
Check mouse feel before and after opening settings menus.
Test a crowded map for hitching.
Confirm weapon pickup no longer forces a switch.
Keep a backup of the exact config that felt best.