So I've had my 24" Al iMac ever since November 2007, good and everything until the past couple days, after extended use of the imac, everything is fine, screen is great, but when entering screensaver, its still great, its like a couple minutes or so into the screen saver when the top of my iMac's screen starts to flicker! When I move the mouse to get out of the screen saver, every thing is back to normal. It happens with all screen savers, what could be going on??
