eMac screen went purple and was shaking and then it just died

Question

eMac screen went purple and was shaking and then it just died

I came home and found an eMac on my back porch, came from my moms friend apparently. so i plugged it in and turned it on and i was playing on it for a while but safari would just repeatedly crash after loading the home page, so i restarted it and it seemed to fix the problem, me and my friend then took the casing off and replaced the cd drive because it was jammed. it started up just fine after that but after the next restart the screen seemed to be "shaking". it was jumping left to right. so i powered it off and started it up again. this time it did the same thing but it was more vigorous and the screen was flashing from normal to a dark purple tint. then it went really dark purple, the screen shut off, then the whole computer shut itself off. now only after leaving it unplugged for at least 30 seconds the first or second push of the power button will "twitch" the fan and the CRT sounds like its trying to come on, but i only get the CRT sound and the fan maybe doing at most a quarter turn before it stops. the only changes made was a new cd drive and a second RAM card. i tried it by pulling out the added ram card and still nothing. then tried with the cd drive IDE cable removed and still nothing. What went wrong and how can i fix it?

eMac-OTHER, Mac OS X (10.3.x)

Posted on Apr 19, 2012 10:46 AM

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Answer 1

Apr 20, 2012 12:26 AM in response to hondasarecool

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.

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Answer 2

Allan Jones

Level 9

68,690 points

Apr 20, 2012 10:36 AM in response to hondasarecool

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:

How to locate the serial number and identify your model

Don't post your serial number here---just use the chart to find your sub-family:

eMac
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,

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Answer 3

Apr 20, 2012 10:39 AM in response to Allan Jones

Sorry I forgot to clarify. The serial number is missing but it had a 1.25ghz processor. It was the first thing I checked. I think it's a 2004 model. If you need any information let me know

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Answer 4

Allan Jones

Level 9

68,690 points

Apr 20, 2012 8:46 PM in response to hondasarecool

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.

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