23" imac has pixelated waves across screen then freezes

I think there is soemthing wrong with the display and anyone has experienced this? I googled and can't find anything to do with this. I don't know what to call it-- wave pixelated display problem?
The screen suddenly shows waves onscreen and i can't do anytihng except force it to shut down.
I have 4 gb 800 mhz DDR2 SDRAM. This computer is old, so I am feeling it is a hardware problem. It has happedn 3 times within 3 hours. It started when I tried to go back in Time Machine to retrieve a file. Then, the next forced reboot was the screen above, then the third time was in my husband's log-in.
I would think I have to make an appt with Apple Genius bar tomorrow.

Have you even heard about this issue before and help me find proper terms in order to search? That is what I am asking before I haul this heavy machine to the Apple store. The nearest apple store is less than 3 miles.
I don't have a warranty(long since expired), nor Apple care, etc. This computer is about 4 years old. I don't even know how to describe this in the search to begin with. I did a search on apple's help section and Googling but nothing comes up that matches this issue. You're not helping me by sending me to imac product FAQ.

Similar Messages

IMac boots to bit-mapped rows of diaganol lines across screen & then freeze

Im not sure where to post this. Unsure if it's a start-up or a display problem - or both ...
A friend of mine was trying to install boot camp on her 17" Early 2006 but the installation failed half-way through ...
Now, when the machine is switched back on - serious square or bit-mapped looking rows of diagonal lines appear from top to bottom on the screen at 30mm gaps ... it boots up OK to the grey Apple Screen with the spinning cog below - then the lines disappear and the blue start-up screen - looks like it's about to show the 'Starting Mac OS X' window - but then stops - and the cursor changes to a weird rectangular mess - and nothing else happens ... the cursor still moves - so I know the system is not completely frozen - it just won't boot past the blue screen ...
The only way I can get it to boot to the desktop is in Safe Mode (shift key at start-up) - but it boots all the way with the diagonal lines.
Here's what I have tried so far ...
* - reset pram
* - targeted it to another intel mac and used Disk Utility to zero the hard disk to a single Mac OS Extended (journaled) partition (erasing the previous XP portion created by the botched Boot Camp assistant).
* - a clean install of Mac OS X.4.6 via a 'C' boot.
* - restarted into safe mode holding the 'shift' key to get to the desktop.
* - run software update to see if there were any new EFI or Firmware updates.
all to no avail ...
I have also scanned the Apple downloads pages and here in the discussions.
And also the Boot Camp discussions - I can find only one other post with a similar issue - but there is no 'fix' or solution posted ...
My hunch is the firmware has been affected by the boot camp installer - or something to do with the EFI parameters on the video board.
I have tried everything Apple suggests - including an attempt to reinstall the firmware via a hard press of the power button and inserting a special install firmware install CD from Apple downloads - but I can't get the firmware bar to load at start up ...
If I try reinstalling the latest firmware update - I get a message saying "Your Firmware is up to date' - or 'This update is not needed on this machine' ...
Q: Is there a stand-alone installer that will reinstall the firmware - without doing a version check - and just do a fresh firmware install ... ?
Does anyone know a way around the version check.
I am convinced this issue is a software/firmware related problem - I sense the EFI settings have screwed up the video settings on the board - and I all i want to do is refresh them.
It's still under it's initial 1 year warranty - but I'm not sure a botched Boot Camp install is covered ...
Sorry for the long post - but I'm hoping a nice apple guru can help me out with this 'very hairy' problem ..
... macfinger - auckland city
17" intel imac early 2006 1.8GHZ 512RM

OK - here's the result of the rows of diagonal lines across the screen on the 17" Intel Core Duo iMac, which I posted last week ...
The logic board was definitely faulty - it could not be repaired by firmware or otherwise ... the service centre was very vague about which area or part of the board failed - but I suspect it was the embedded video board or VRAM ...
(actually - I still reckon it was a botched firmware - but seeing as Apple's 'Open Firmware' is nor strictly 'Closed Firmware' .... there was no way of actually testing that theory for sure ...
From what my friend has told me - she said this fault was the result of a botched Boot Camp XP installation when loading the Windows drivers from the Mac generated Drivers Install CD which froze - and then trying to boot back into Mac OS X by doing a hard restart, after it failed ...
A message to any future readers of this post:
If your machine shows signs of of the above symptoms - you'll have to return it to an Authorised Apple Service Centre to have the logic board replaced (hopefully under warranty) ...
BE SURE AND BACK UP ALL OF YOUR PERSONAL USER DATA FIRST - AS THERE WILL BE NO GUARANTEE YOUR USER FOLDER WILL BE RETAINED WHEN YOU GET YOUR MACHINE BACK ...
You can still access your HD by doing a safe boot: hold the 'Apple' & 'S' keys immediately after you hear the start-up 'chimes' ....
Once you're back to your desktop - use your machines internal CD-RW/DVD to copy your files to disk ... it's a bit tricky with all the lines across the screen - but persevere - 'cause that's what we did - and we know it can be done.
Good luck ...

My imac starts with a white screen, then goes black and a small white line just blinks in the top left corner of the screen?

My imac starts with a white screen, then goes to black with a small white line blinking in the top left corner of the screen. Any ideas? Thanks.

Try starting your iMac with the original DVD that came with the machine then launch disk utility to repair your hard drive.

IMac keep shutting down black screen then have to hold power button down then turn it on again i did this 4 times in all of a period of 5 minutes what to do ??

iMac keep shutting down black screen then have to hold power button down then turn it on again i did this 4 times in all of a period of 15 minutes what to do ??

Hmm. The problem still may be the RAM - Apple buys the RAM it puts in its machines from third-party vendors (usually Hynix) so it could be a RAM problem.
There are a couple of things that you can do yourself before taking your machine into an Apple Store or an AASP... download and run an application named Rember that will run a RAM test for you - let it run for a couple of hours or even overnight. If it turns out that your RAM is faulty, Rember will let you know. If it is faulty, then you have a couple of options - replace the RAM yourself or (particularly if you're under warranty still) take the machine to an Apple Store or AASP and have them replace the RAM.
If Rember finds no fault with the RAM, then you'll need to take it into an Apple Store/AASP and get a free diagnosis on the machine. Three beeps do usually indicate faulty RAM, but if it tests good with Rember you likely have another problem - it could be something as simple as the RAM, somehow, not seated correctly or signs of another hardware problem.
Run Rember first... call back with results.
Good luck,
Clinton

New imac displays horizontal grey bars and green pixels on startup and then freezes on a light grey screen

This is happening on a brand new 21 inch imac, all new specs released a few days ago.
This happened the first time I started up the imac straight out of the box. The screen displays alternating light and dark grey bars with green pixel specs all over it. The apple symbol and and loading symbol are visible too - but it then goes to a light grey screen and freezes.
If I manualy restart it will then startup normaly but will do this next time I startup the machine from a cold start.
Does anyone else have this issue. This is my first mac and it doesn't seem acceptable to me. I think I've been sent a dud!
Any help / opinions would be helpful. Cheers

I wouldn't try to solve this issue by troubleshooting a brand new machine. My personal policy is if an electronic device is malfunctioning out of the box, I return it for a replacement. We're talking about an expensive purchase and it should work, but even with stringent quality control a small number of products will fail out of the box. You didn't mention whether you ordered it online or purchased it at an Apple store. If you can, get a new machine at an Apple store and take advantage of the free setup. An Apple salesperson will start it in the store, so you'll know before leaving if it's good.

My macbook pro keeps flashing green lines across the screen then freezing, can anyone help?

Back in December my macbook started doing this thing quite regularly where it would flash black or green lines all across the screen, for maybe half a second, then the screen would freeze, so I would power it down manually then back on again. I took it into a store and paid a lot of money for them to "fix" it, but when I got it back it was still doing it. I just recently took it in to a different store and the guy said he couldn't reproduce the problem, but replaced the RAM and gave it back to me. Within a day of having it back the same thing happened, twice. At this point I'm not sure what to do, the money I spent on "fixing" it could almost have bought me a new one. The most recent time I shut it off, when it was turning back on it stopped on the grey screen with the apple and started making a continuous beeping sound, which I took a video of. Does anybody know why any of this is happening??

Hi Were you using the apple store for the repairs you had done? As to the point of taking in to a store to have it repaired and getting it back with the same problem. It should have been taken back to the same store as they have to stand behind what they do. You do not say what they repaired. The store replacing ram without knowing what the problem is ,is questionable. If you are going to change ram for the original apple installed ram, you need to make sure it is compatible with your MBP. One of the best sources for this is Macsales.com. As to the Beeping sounds here is a link on it. You do not say if this is one continuing beep or more than one repeating itself.http://support.apple.com/en-us/HT202768

Macbook Pro Black boxes across screen then crashes

I have a Macbook Pro that I got 2 months ago. A couple days ago it froze and had black boxes all across the screen, then it crashed. Today when I started it up after I logged in while it was loading the black boxes popped up again, then it crashed. And when I tried to restart it it just beeped. The battery was around 50% so it wasn't dead. Its been fully updated and I haven't made any changes to it. Please help if there's anything I can do without taking it in

A new Mac comes with 90 days of free tech support from AppleCare.
AppleCare: 1-800-275-2273
Best.

My iMac has a Kernel Panic screen come up on start up and I can't get past it no matter what I try. Any help to fix this would be greatly appreciated.

My mac has a "Kernel Panic" screen come up on start up. No matter what I try I can't get past this to fix it. Any hints out there? Do I have to completely wipe my drive and re-install to fix this? I can't even back up my files before doing this as like I say I can't get past the Kernel Panic message.

There are some fairly informative articles about kernel panics...
•OS X: About kernel panics:
http://support.apple.com/kb/TS3742?viewlocale=en_US&locale=en_US
Note the toggle triangles to get more info in the above article, some are
important steps, with alternative methods of accessing or performing a
suggested activity and may vary with the OS X version in use.
•Resolving Kernel Panics:
http://www.thexlab.com/faqs/kernelpanics.html
•Technical Note: TN2063: Understanding and Debugging Kernel Panics:
https://developer.apple.com/library/mac/technotes/tn2063/_index.html
The above TN covers several technical aspects to identify & troubleshoot.
Some are above the average user needs, but still can be rather helpful.
Hopefully you can get past the kernel panic screen, there are several
ways to attempt to do that, however if the issue is hardware, a reinstall
of the OS X may not cure the underlying cause of the symptom.
Good luck & happy computing!

Pixel line across screen

My laptop sudden has a pixel line running fully across the screen from the left of the screen to the right. I have rebooted, updated drivers, used pixel repair software and tried to rub the pixels clear. which makes me believe its possibly a hardware issue. Has anyone else con across this problem or know what could be wrong?

Contact HP in your region. It may be hardware display issue.
Have a look at this:
http://h10025.www1.hp.com/ewfrf/wc/document?cc=uk&lc=en&docname=c01881110
++Please click KUDOS / White thumb to say thanks
++Please click ACCEPT AS SOLUTION to help others, find this solution faster
**I'm a Volunteer, I do not work for HP**

IMac Display -- White band across screen

I recently noticed a white band across the top half of my screen. The line is about 3-5 tall and runs the entire width of the screen. This is incredibly annoying. The so-called Genius at the Apple store said I would have to pay about $800 to replace the display, which is ridiculous. It is time that Apple match product quality with design quality or fix these problems.

I have the same issue.. although it isn't terribly noticeable yet... It has crept up using this computer for a month. The computer has only been in use for 1-1/2 months. I have multiple band running width wise down the entire screen.

IMac has question mark on screen

My 17" iMac running Panther is usually kept in sleep mode but today I walked by it and it sounded like the fan was racing. I rebooted it and the fan racing stopped. Unfortunately when it rebooted the screen came up blank with a an icon of a folder with a question mark on it. Is this a software or hardware issue?
Thanks for anybody's help.

Could be either or both.
You can start the computer up from the Install disc DVD and see if Disk Utility
ran from there, can verify and/or 'repair disk.' You can also see about booting
up in SafeBoot mode and if the machine does respond eventually, see about
checking the choice in System Preferences> Startup Disk, if it's still the Mac HD.
The hard disk drive could be failing; or the Directory on the hard disk drive.
If the drive is original equipment and the computer more than 3 years old,
there is a possibility the drive could be failing; or there are read/write errors
on the drive, or bad sectors, etc. And if you have a full backup of the Mac HD
contents, you could consider seeing if Disk Utility can be used to Secure Erase
the computer's hard disk drive (over-write with zeros, one or more passes) and
then choose the partition map, and reformat the drive; then reinstall the OS X.
However, the simple things are obviously best tried first; even if you do have a
means of restoring from a clone, & have a clone on an external hard disk drive.
Or, if you have a retail copy of Disk Warrior on DVD or CD for your OS X, it may
be a good idea to see if it can find fault & repair hard drive Directory issues.
Of course, there are other possibilities, depending on your skill & means.
Perhaps other readers will have quicker ideas on this topic?
{Which iMac build version (specs) do you have this issue with? Is there an a copy
of the original Apple Hardware Test on CD or on the boot DVD? If so, test with it.}
Good luck & happy computing!
{edited}

IPhone 3G has horizontal line across screen

Today my iPhone developed a line across the screen where the colour is inverted all the time. A restart and a reset have not fixed it. Anyone else had this? Any cure or do I need to send it back (again)?

You will need to send it back or visit a local genius bar. They will do a restore on your phone before replacing it, I had this issue once. Good luck

Help! My Imac has a very wierd screen problem!

Hey all Mac users.
I really hope that someone here can help me. A few minutes ago my screen went totally bananas! I was using photoshop when it happened. It didn't seem that my programs were affected, just my screen. I could see my mouse and move it on the screen.
This is the first time a thing like this has happened. I manually turned off the computer to restart it.
Here's a picture of what it looked like:
A friend told me that i should get a hardware/memory test but i think you need a cd for that or something? I am so bad at these computer problems..
I really hope that someone can tell me what's going on with my mac. I really don't hope that it will happen again!

Yes there is a hardware test you can run. Quite possibly it's still on the hard drive's hidden partition if you don't have the disks. More information about that here: http://support.apple.com/kb/HT1883
So what happened after you restarted the computer? Does - or did - the problem only occur while running Photoshop? If it has only happened once I'd wait and see if it does it again. It may have been just a one time glitch.

Imac has two lines runningthrough screen, sometimes there is more

my imac had one fine black line going from one side to the other side of the screen, now there is two. i can see a third line that is starting to get darker. software is up to date and comp gets restared
please give me advice?
regards
sonja

AppleCare's Express Lane. Do note that if you're within 50 miles (80 KM) of an Apple repair station, you're eligible for onsite repair since yours is a desktop machine. Might have to search AppleCare's pages if you're not in the US, which I suspect by your username.

IMac has a half darkened screen

My new iMac is about a month old. Last night it started displaying at about half its intended brightness...as if it is stuck in the transitional energy saving mode. I keep restarting, but it won't go back to normal.
This is the second major problem I've had with the new iMac (first was a bad firewire port and they had to replace the machine).
Thanks for any help or suggestions
Sarah

Have you checked the brightness setting in System Preferences?

23" imac has pixelated waves across screen then freezes

Similar Messages

Maybe you are looking for