I want to use 1024 x 640, but the lowest I can select that matches my display is 1280 x 800. 1152 x 870 or 1024 x 768 options are available, but those distort the graphics.
The default resolution that was selected when I first loaded the game was the correct aspect ratio, just higher than I'd like. I want to use a lower resolution since it'll reduce the heat generation, and it doesn't make a visual difference for me. The heat is comparable to playing the mmog!