Why does my eMac lock-up unpredictably?

Posted on 2008-10-17
Last Modified: 2013-11-24
After years of trouble free operation, my pals eMac freezes, forcing me to use the power-off button to restart.  When it locks-up, very often the screen presents a highly jagged image (the scan raster appears to be out of sync at this point) and nothing is legible or operable.  Even the cursor is locked in position. The fault can occur at the blue stage of booting or much later when opening or attempting to use one of the applications.

I've clean-installed the Mac OSX (10.4.11) op system without any additional software or re-installation of clients files.

No USB or FireWire accessories (apart from the keyboard & mouse) are refitted.  I've tried using my own eMac trusty keyboard and mouse too without discernible difference.

I've run TechToolPro4's advanced test regime, repeatedly and no errors are found.

What do I do next please?
Question by:JeepneyMan
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 3
LVL 53

Expert Comment

ID: 22741282
How much free space do you have on the hard drive?
LVL 12

Accepted Solution

alikaz3 earned 504 total points
ID: 22741677
>> very often the screen presents a highly jagged image

Sounds like a hardware video error to me, which could either be a faulty video chip/video memory, or the heating device has failed/clogged up. I'd take the system apart and clean it out, if you do not feel comfortable doing this (I just took a look at a picture of an eMac, looks difficult) you may want to take it to a computer shop or private technician. If the video chip is being cooled properly, then it is probably faulty requiring a replacement. I just read this:
"To Apple's detriment, a number of eMac machines have suffered from what was known as "Raster Shift", a strange phenomenon where the bottom third or half of the screen goes black, with the rest of image shifting upward and out of the top boundary of the display. Serious static also accompanies the problem, rendering the viewable part of the screen virtually useless. In response to the problem, Apple offered a solution which involved the replacement of a video cable inside the eMac's case."

Is that what you are experiencing?
LVL 12

Assisted Solution

alikaz3 earned 504 total points
ID: 22741679

specs on your model
Space-Age Communications Transitions to DevOps

ViaSat, a global provider of satellite and wireless communications, securely connects businesses, governments, and organizations to the Internet. Learn how ViaSat’s Network Solutions Engineer, drove the transition from a traditional network support to a DevOps-centric model.

LVL 12

Assisted Solution

alikaz3 earned 504 total points
ID: 22741743
here's some dissasembly instructions (for the DVD portion at least):

here's the infamous cable for sale:

wow, and here's some "helpful" info:
>>i tightened some more screws and slapped it a few times and that did the trick.

this seems like a common issue

Author Comment

ID: 22744648
Hi alikaz3!

Your suggestions seem spot on.. That's fantastic info and I really am grateful. Although the screen fault is not quite like it is explained in your initial response, something tells me it is a raster issue. I shall strip the unit open and clean it all out and follow up the leads and links you've very ably given me... It's a little late for me here in France now, but I shall attempt this tomorrow (Saturday) and get back to you with an update..

Funnily enough I wondered about the dirt and dust issue (I've always cleaned out my own machines including my eMac) but was hesitant about stripping this guys unit. Now I'm going to try it and check that connector out too.

Thanks again for a sensible and coherent reply.. Have a good evening and I'll be back to you tomorrow...

Kind regards to you.
LVL 12

Expert Comment

ID: 22744725
I'm glad I was of help! Post back with what you find

Author Comment

ID: 22744854
Hi Strung!

This 40GB eMac has had a clean install and currently only has the OS on it as explained in my initial query. I have not loaded any other files or apps.

So overal the HD is over 75% empty.

Thanks for your thoughts though!

Author Comment

ID: 22762973
Hi Alikaz3 and Strung!

My apologies for not replying sooner but unexpected family illness diverted my attention over the weekend. I hope to return to this query tomorrow (Tuesday) and ask that you kindly stay with me while I check out the options against the kit in question.

Thanks for your patience and help so far..


Featured Post

Free Tool: Port Scanner

Check which ports are open to the outside world. Helps make sure that your firewall rules are working as intended.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

The /etc/authorization file in Mac OS X 10.x can be used to control access to the various panes of the System Preferences amongst other things. It’s used by some of us Mac Sys Admin’s to give Standard Users access to System Prefs panes that only adm…
Thanks to luck and dedication (hitting refresh every 5 seconds when the pre-orders were going live at midnight on April 10th) I managed to actually receive an Apple Watch on release day, April 24th. Which means I’ve been using it daily for just ov…
This Micro Tutorial hows how you can integrate  Mac OSX to a Windows Active Directory Domain. Apple has made it easy to allow users to bind their macs to a windows domain with relative ease. The following video show how to bind OSX Mavericks to …
I've attached the XLSM Excel spreadsheet I used in the video and also text files containing the macros used below.…

740 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question