Well it seems my 2010 mini just gave up the ghost. When I hit the power button, I get the familiar chime followed by nothing. No video, no response to keyboard commands. Tried an SMC reset but it did not help. Could not do a PRAM reset due to the lack of keyboard response. Tried another keyboard and USB ports also. No change. The funny thing is what took place just prior to this when it was still working. I had just installed BootChamp so I can get to my Windows system faster. I received an error message about the "drive not being blessed". I then quit and tried to change the default startup disk but that gave an error also. I later found out this is a problem BootChamp users are having with El Capitan but I have Mavericks on this mini. Strange. Anyway, I ended up just restarting the mac and that brings me to where I am now. Also tried inserting a bootable system disc. It was able to grab the disc and spin it up but nothing after that. Bad logic board perhaps??