My apologies if I'm posting this in the wrong forum. Please feel free to move it if needed. Background: I have an Intel iMac that I purchased in the summer of 2006. I love the thing and it's finally given me the first hiccup: it won't turn on. I had the same problem a few weeks back, but after resetting the SMU and screwing with it for a while it turned back on. I don't often turn my computer off, other than restarting, so it probably hasn't been shut down since then. I'm not sure if it's relevant, but I upgraded to Snow Leopard this afternoon (everything went fine, I used it afterwards). Tonight I popped a breaker, so my iMac turned off. Since then, it won't turn on. It's the same symptom as before, but no amount of unplugging/plugging, resetting the SMU, and popping the RAM out and back in will help. So after much reading, I assume it's either my logic board or power supply. Based on what I've read it seems like the power supply is typically at fault when it won't turn on at all. The logic board is usually at fault when it randomly turns off and other wacky things. Other than the fact that it won't turn on, I haven't had any problems. Do you think it's my logic board, power supply, or something else? Any diagnostic techniques that you know of that might be able to help me out? I'm about 7/10 on a tech scale and wouldn't be completely against opening the thing up, but would prefer not to. Thanks in advance! EDIT: It was on a surge protector, so I don't think that's the problem. I tried different outlets too. The computer does not respond at all when I push the power button.