X and desktop backgrounds
I recently found some cool desktop backgrounds for Slackware.
But when I choose a jpeg or png file to use as my desktop background, it looks fine at first. However, when my computer goes to sleep for any length of time and then wakes up, the screen "real estate" is larger then the desktop and I have to recalibrate the monitor to get the screen to fit in the monitor correctly.
Put another way, when the computer wakes up, sometimes (though not all) I can place my cursor against one side of the desktop and it will move as if the background is larger than the screen.
What can I do to keep the screen at the same size as the monitor when setting my own background?