+r_width xxxx +r_height yyyy
+r_width 1920 +r_height 1200
If you still can't get the game working, run it in Vista SP2 compatibility mode.
If you get an error saying 'This program has stopped responding' after changing between fullscreen and windowed, force DX9 mode to solve the issue.
C:\Program Files (x86)\RivaTuner Statistics Server\Profiles
Game will not launch at all and ends up with security error 5024. You are probably running Process Explorer so turn it off and game will launch OK.
In the mission "Recovery", there's a rather common bug where you'll get no objectives after destroying the two tanks and Psycho and the hostage just hang out in the school building. If that happens, you can restart the mission. If that doesn't fix it or if you rather don't, you can manually proceed to the end of the area and finish the level, it isn't too long anymore and you should not miss out on vital bits.
To do so, run to the south east of the village. There should be a waterfall. Use the strength augumentation to scale it and follow the river on top (also seen on the map) to the very end. It will be a rather long walk and you'll come across other waterfalls that you have to jump up, also there will be several big groups of enemies on the way, so be careful. Just always follow the river and you will finally come to yet another waterfall, which has a large cave to the right of it (you can't miss it). Going into that cave triggers the end of the level and you'll proceed to the next mission where everything will work as usual.
The way to walk is illustrated here, courtesy of Affenzahn375 from here.
You can change your refresh rate manually each time you open and close the game.
You can automate this with QRes:
timeout /t 10 > NUL
timeout /t 60 > NUL
tasklist /FI "IMAGENAME eq crysis64.exe" | findstr = > NUL || goto _cleanup
timeout /t 5 > NUL
The console can be opened with ~, but the available commands are limited. This limitation can be bypassed by the con_restricted=0 command or by adding -devmode to the game's shortcut. A thorough list of console commands can be found here.
Instead of re-entering console commands every time the game starts, the file <path-to-game>\system.cfg can be created to apply console commands automatically. The commands need to be formatted differently in the file, using an equal sign instead of a space. For example, to change the FOV to 80 you would use cl_fov=80 rather than "cl_fov 80" like in the console.