You probably did not do anything wrong. CRT displays, and the power circuits that provides the very high voltage needed to run the CRT, are like old TV sets. Eventually, they go bad.
Or it may be the power supply failing. In that case, the entire computer may shut off expectedly, probably designed that way for safety reasons. Unplugging it may have reset the power supply, and it can attempt to start up again.
I would not try any repairs that expose the back end of the CRT. The voltages there can be very dangerous, and they remain even if the eMac is unplugged from power.
There are two variants of the eMac that had significant hardware issues over many units;
1) The first gen eMacs with 700 and 800 mhz processors and nVidea graphics (shipped in Jan to midsummer 2002) had bad IVAD cables that caused significant video distortion. The 'collapse-to-center' was a common failure, oftern accompanied by odd popping or cracking sounds from the CRT. Image shaking was not unknown.
2) The USB 2.0 eMacs with 1.25gHz processors (some special-order USB2 units with 1gHz processors also) had a serious logic board issue that is, today, basically fatal due to lack of non-affected parts.
We need to know which of the four eMac sub-familes you have to provide any additional suggestions. Please find out how to tell in this Apple article:
Don't post your serial number here---just use the chart to find your sub-family:
- eMac (ATI Graphics)
- eMac (USB 2.0)
- eMac (2005)
Note: If your serial number starts with "R" or "RM" then the computer is a factory refurb and the chart won't help.
and provide the family name. Then we can see if you have one of the known issues,
The serial number is missing but it had a 1.25ghz processor. It was the first thing I checked.
That pins it to the "USB 2.0" but not the "2005" and puts you in a group of computers that could have bad logic boards.
If the computer runs long enough to do "About this Mac" you can read your serial number onscreen. In the "About" window:
Click twice on the smaller gray text "Version 10.X.X" under the bold "Mac OS X" and the serial number will appear in that spot.
If you find it that way, compare to this list of number ranges where affeected boards are dound"
- • G8412xxxxxx- G8520xxxxxx
- YM412xxxxxx - YM520xxxxxx
- VM440xxxxxx - VM516xxxxxx
If within those ranges, you could well be facing repairs that either can't be done for lack of parts or are prohibitively expensive. Distorted or not video was a major symptom of the bad USB 2.0 logic boards.
If you live within driving distance of Eugene, Oregon USA there may be an affordable repair option. If so, post back and I've tell you what I know about that option.