Tools:
-benchmark: Runs the benchmark tool and immediately exits game.
-help: Display list of all command line options

Graphics:
-renderquality: Set the render quality of the game.
-shadowdensity: Set the shadow density of the game.
-texturequality: Set the texture quality of the game.
-viewdistance: Set the view distance of the game.
-detailquality: Set the detail quality of the game.
-novblank: Disable wait for vblank (No Vsync)
-norestrictions: Do not limit graphics settings
-width: Set width of main render window (default is 800)
-height: Set height of main render window (default is 600)
-safemode: Run the graphics in the lowest setting possible
-frameLimit: Limit frame to interval of refresh rate (ex If refreshrate is 60HZ –frameLimit 1 = Locks down to 60HZ)
-refreshrate: Set the refresh rate of main render window – Warning - Monitor must support (ex. –refreshrate 60)
-fullscreen: Force fullscreen mode
-windowed: Force windowed mode
-availablevidmem: Set amount of physical Video Memory(ex. –availablevidmem 0.9)
-percentvidmem: Percentage of video memory to make available to GTA

Audio:
-fullspecaudio: Force high-end CPU audio footprint
-minspecaudio: Force low-end CPU audio footprint

System:
-noprecache: Disable precache of resources
-nomemrestrict: Disable memory restrictions