We aren't saying turn it off. We are saying it's the answer to your question.
You asked why do my graphics look this way.
(Well, Ashley did, but he only meant so you could see the graphics show at the right size with scaling turned off.)
leysanity was saying if you make the graphic twice and big, 800x1600 rather than 400x800, it will be clearer when it doubles in size. Because it's actually showing at the new original size. 1600 is a bit big though, that's the balance I was referring to.
96 dpi is the same as 300 dpi if you are looking at a 400x800 image. That's just a number used to calculate how many inches wide the image would be.
400 pixels 96dpi would print at 4.1 inches.
400 pixels 300dpi would print at 1.3 inches.
They are both 400 pixels on screen.