Delete your DoomConfig.cfg, run the game so it builds another one, then open the file with wordpad and tweak those setting and remember to restart the engine with vid_restart when you make the changes: 

Change to 1 to enable 0 to disable; 

com_drawfps = 1 Draws Fps counter 
com_maxfps = 125 (any number) Limits Fps 
com_drawhud = 0 Enables drawing of heads up display, disabling should help improve fps a little bit 

Adjust those three next according to how much memory you got: 
com_preloadDemos = 0 
r_varmegs = 92 
s_cacheSize = 16 

Those 4 next are the ones that make Doom3 juicy, so don't disable them unless you have serious performance problems and you wanna experience the game with all the visuals tuned down: 

r_diffuse = 0 Enables diffuse mapping (Disable for speed, enable for quality) 
r_skipBump = 1 I guess that disables bump mapping when on 
r_specular = 0 Enables specular mapping (Disable for speed, enable for quality) 
r_useStandardGL = 0 Disables bump mapping and maybe more 


The next 4 ones are about your hardware and drivers: 

r_useParhelia = 0 Enable if you got a matrox parhelia graphics card 
r_useNV20 = 1 Enable if you got a Gf3-Gf4Ti graphics card 
r_useNV30 = 0 You wouldn't need instructions for that 
r_useGL2 = 0 Don't enable it unless you got beta drivers with OpenGL2 support 

r_mode = 2 Changes the resolution( 1=400x300, 2=512x384, 3=640x480, 4=800x600, 5=1024x768, 6=1152x864, 7=1280x1024) 

r_depthbits = 16 or 24 Changes z-buffer bits (you should be able to lower it to 16bits on Gf3 and above even if r_colorbits = 32) 

r_stencilbits = 0 or 8 Changes stencil buffer bits (setting it to 0 should disable stencil shadows, not so sure if the game would still work) 

r_colorbits = 16 Changes colorbits, lower it to 16 if you got Gf-Gf2mx-Gf2gts.. 

r_ext_compress_textures = 1 Enables texture compressing, enable it unless you have a 128mb graphics card (Enable for speed, disable for quality) 

r_ext_texture_filter_anis
otropic = 0 Enables anisotropic filtering (Disable for speed, enable for quality) 

r_fullscreen = 1 Enables fullscreen 

image_filter = GL_LINEAR_MIPMAP_NEAREST Changes texture filtering methode (change to GL_LINEAR_MIPMAP_NEAREST for better performance, default is GL_LINEAR_MIPMAP_LINEAR and improves quality) 

r_shadows 0 Shadows on/off (Disable for speed, enable for quality) 

r_useOptimizedShadows = 1 
r_useExternalShadows = 1 
image_usePrecompressedTex
tures "1" 
image_useAllFormats "1" 
image_compressBump "1" 
image_compressSpecular "1" 
image_compressDiffuse "1" 
image_preload "1" 
image_depth "2" 
image_colorMipLevels "0" 
image_anisotropy "0" 

Those cvars could also help with your performance 


I'm stuck on dial-up so i haven't try those setting yet, gimme some feedback about them. 

? you screw up somehow, you can always delete your DoomConfig.cfg and let the game build another one. 



e3_demo3 "activate_demo3" 
e3_demo2 "activate_demo2" 
e3_demo1 "activate_demo1" 
e3_intro "e3\intro" 

hk "monster_demon_hellknight" 
lost "monster_demon_lostsoul" 
mag "monster_demon_maggot" 
mancubus "monster_demon_mancubus" 
sentry1 "monster_sentry1" 
zsec2 "monster_zombie_security2" 
zsec "monster_zombie_security" 
bruiser "monster_demon_bruiser" 
zct "monster_zombie_commando" 
zcc " monster_zombie_commando_c
gun" 
rev "monster_demon_revenant" 
zmaint "monster_zombie_maint" 
zfat2 "monster_zombie_fat2" 
zfat "monster_zombie_fat" 
imp "monster_demon_imp" 
pinky "monster_demon_pinky" 

Those seem to be shortcut names, try to spawn a lostsoul.