lucy24 - 12:24 pm on Mar 7, 2012 (gmt 0)
Yes, you confused me by mistyping "repeat-x". The only way I could get that to work was with a solid color and then it made no sense to talk about images :)
If it's a gradient that only changes in one direction, then making it 1px high is definitely the way to go. It does make editing a little tricky because you can't really see it. I mean editing the image itself, not the page it lives on.
You could experiment a little and see how much the filesize changes as you go from 1 to 2 to 4px high. It will get bigger but it won't be 4 times as big. Also be sure to try both png and jpg; sometimes there's a really big difference between formats, depending on what type of image it is. For a gradient, you're probably best off with jpg, but you can compress it a lot since it's meant to be fuzzy anyway.