e) If editing the Config memory didn't help, or the game just doesn't use one, you can try to change resolution via RAM edit while being in game. However, it may be dangerous to your graphics card driver, so use this method with care.
Unlike the Config memory method, replacing values in deeper parts of RAM isn't recommended.
Also, if you've replaced a correct value, the resolution may not be changed, when you go back to the game. Sometimes, you have to select the replaced resolution in game options again, or start a level to apply your change.
Some games doesn't save the new resolution, so you'll have to edit the RAM after every game launch.