Grand Theft Auto IV - Remove Graphics Settings Restriction

When you attempt to change the graphical settings in GTA IV, you may get the following error which doesn't allow to make any changes:

Warning! Your graphics settings are near, or exceed, the suggested resource limits for your system. It is recommended that you reduce your graphic settings in order to run the game optimally.

This error may appear even on high-end  graphics cards. To fix this, see the instructions below:

1. In your Steam Game Library, find the game, right click it and click Properties.
2. Click the "Set launch options..." button.
3. Type in -norestrictions -nomemrestrict and click OK.
4. Click Close.