Green light stays on, no video, no HDD led

I recently tried to upgrade my CECHL01 from the 80Gb HDD, to a 500Gb. now I cannot get anything from my video on HDMI or AVI. Also only have a couple of blinks from the HDD every so often. I have taken it apart, cleaned it, and repasted the sinks. My PS3 does not do the video reset by holding the power button down after it turns on either. Any suggestions?