Wirelessly posted My friend has an older iMac (2005) running Tiger 10.4. He finds that every few minutes whilst he's using it, the screen dims and a plus symbol appears at the bottom right of the screen. I had a look for him but couldn't figure out why it was doing this. Has anyone else seen this? Btw. I should add that even though it is a fairly old iMac, with just a 700mhz processor, the startup time and general speed of performance were awesome!