01-29-2014, 12:31 PM

Hi guys, I have an old 2007 White iMac, it is a 20" Core 2 Duo. I just upgraded the hard disk to a 1tb drive. When I plugged the power cable in, I had a spark come from the top left of the mac (which is an inch or two above the power circuit board)

Now I have no power at all, I cant switch it on at all.

Anyone have any ideas?

01-29-2014, 12:43 PM

Have you opened it back up...to see what wasn't reassembled properly (since this spark) would not have happened if everything was put back together correctly?

If the spark came from the top corner area...this is where the power supply is located in some of the older white iMac's.

I'm guessing the power supply got fried. And of course...it would need to be replaced. But first...the reason for this problem needs to be corrected...or a replacement power supply will be damaged as well.

Once you have power to the unit...then you will have to see if the computer works. Since you never know...the logic board could have been damaged as well.

- Nick

01-29-2014, 12:54 PM

Thank you nick. I think you are correct. To confirm the worst of my fears. It is a shame its so old now. Maybe time for an upgrade.

01-29-2014, 01:05 PM

Originally Posted by rjevans83

Thank you nick. I think you are correct. To confirm the worst of my fears. It is a shame its so old now. Maybe time for an upgrade.

I have a couple older White Intel iMac's...and they can certainly still get some jobs done (older games, older versions of MS Office, internet browsing, e-mail, etc.).

Depending on the cost of a replacement power supply (they can be anywhere from $50-$150...gotta check eBay)...it may or may not be worth repairing (compared to the computers used value).

If you can get a replacement power supply for a reasonable price...I would say it is worth giving it a try. But like I mentioned...it is possible that the logic board got damaged (won't know until you can get power to the unit)...AND the problem that caused the power supply issue needs to be taken care of (maybe a loose wire, maybe a loose screw, etc.).

- Nick

01-29-2014, 05:26 PM

Go for the upgrade. Would your home contents insurance cover some of the cost?

01-29-2014, 06:04 PM

I wonder if when putting it back together if a screw was dropped into the machine around the area where you saw the spark? Worth checking as changing the hard drive should not cause that issue.

01-29-2014, 08:13 PM

Worth checking as changing the hard drive should not cause that issue.

Either a metal screw as you suggest Dennis, or more likely incorrect assembly of the chassis when putting everything back together causing a short at the PS ground. I've seen that happen many times in my electronic repair days.