Hopefully someone can help with this problem we have on a customer iMac - its a 24inch aluminium running OS 10.5.8 Leopard. This was dropped off to me with random graphical issues and a sick hard drive. We had the drive cloned and replaced but the problem with the graphics has continued. If you have a message box with an OK/CANCEL style buttons on it the buttons will have black boxes over the top. Likewise, when you boot up the background to the users lists is black. The address bar in Safari is black too. I can click in there and highlight the text and remove it but its still odd: http://flic.kr/p/abadMU Here is the other end of the Safari toolbar with graphic distortion. http://flic.kr/p/ab7nmM Any ideas? I'm going to timemachine back it up tonight and reinstall the OS but I'd rather not if I don't have to. Would be nice to reinstall the graphics driver if possible or force it to re-download through Apple Update. Any ideas appreciated.