I have a 20" iMac, and just purchased a Samsung SyncMaster 2043BWX 20" monitor. It is one of the very few 20" monitors available with the same resolution as the mac monitor, and I'd prefer for them to be the same size. The new monitor is hooked up through my mini dvi with an adapter to standard dvi on the monitor. My iMac has found the monitor, I can set the resolution settings on it, and I can run my mouse cursor right off of my screen onto the new one, however the new screen just remains black. I know that it can't be broken because if I switch the source a message pops up on the screen saying to check my signal cable, which obviously also allows me to see that the screen does have color on it. I'm assuming my connections are also fine since my computer detects the monitor being connected. Any ideas as to what might be wrong? I need some troubleshooting advice and don't want to pay Apple $50 for their assistance... Thanks!