This video show you how to open top cover on an HP ProDesk 600 G1 & G1 Desktop Mini Cette Vidéo vous montre comment ouvrir un HP ProDesk 600 G1 & G1 mini ordinateur
I've never check for that. I will take a look this week if I put hand on this model. I suppose your power Supply is Ok ? Do you hear some "beep" sound or something like that ? or blinking led ?