To get the Quake 4 Cheats,download the AutoExce file right here:

Http://www.games-fusion.net/files/quake4/AutoExec.zip

(Put it in C/Program Files/id software/Quake4/q4base)

Then, open Quake 4 and play single player and then press ` to open the game console and then type in these cheats:

God - God mode
Noclip - No clip
Notarget - Invisibility
Freeze - Freeze everything
Give all - All weapons and ammo
Give ammo - Full ammo
Map [map name] - Load a map (see the list below)
Benchmark - Game benchmark
Com_drawfps 1 - Show FPS
AviDemo - Saves a demo of your playing to an AVI movie file
Gfxinfo - Graphics card infomation
R_gamma [0-3] - Set gamma level
R_brightness [number] - Set brightness level
S_volume_db [number] - Set sound volume (default is 0)
S_showlevelmeter 1 - Toggle sound level display (use 0 to disable this code)
G_showprojectilepct 1 - Toggle hit % to HUD (use 0 to disable this code)
Killmonsters - Kill all monsters
Kill - Suicide
Quit - Quit game