Alright so I did it, I successfully opened my iMac, replaced the internal HDD, and closed it! yay It won't turn on now There was no static discharge during the process so I doubt anything is fried, and all I did was get at the HDD, nothing else. Any possible ideas on what this could be? Of course it could mean it is completely dead, but maybe i'm missing something, or maybe there is a way to get it going again. I looked up resetting the SMU on apple.com support, but that process seems to be for older G-series iMacs.