Works great if you use Optimized for Low-end PC mode
Lag (FPS) is an issue when you are in open world specially if you're in a 24 man dungeon.
So, to alleviate this I suggest you use the "Optimized for Low-end PC mode" from the settings.
Then by default, your client will be resized to 800x600. There's no other way to resize the client after that.
This is where this tool come in handy, it will resize the client for you.
First things first, you need
installed in your operating system for this tool to work.
How to use:
Just drag the slider to adjust resolution.
Note: Uses AutoIt Library, not packed. And see how paranoid VirutTotal is. lol