What is wrong with my iMac? (video corruption, unstable)

I have a 24" Early 2009 iMac.

Throughout "intensive" usage (such as Photoshop, WebGL, etc), the system begins to come to be really unpredictable, causing peculiar graphics corruption and also various other unusual practices. Inevitably, the equipment ices up or collapses.

In some way I took care of to take a screenshot prior to it dropped, and also I was stunned that it recorded the carnage. I've censored (obscured out) some names to shield the innocent, yet all the various other problems become part of the corruption.

I ran a temperature level display behind-the-scenes throughout usage, and also although it raised (as anticipated), it really did not appear to show abnormally high analyses for any kind of parts.

Any person have any kind of suggestion what could be incorrect? Should I attempt re-installing OS X from square one, or is this most definitely an equipment concern?


  • 2.93 Ghz Intel Core 2 Duo
  • 4GB RAM
  • GeForce GT 120 256MB
  • OS X 10.8 (updated from Leopard, after that Snow Leopard)


Having claimed that the parts' temperature levels appeared well acted, I have actually begun to see that the trouble takes place quicker when my area is warmer. Wondering if it is a warmth - relevant trouble


Reinstalled OS X from square one, yet trouble lingers. I assume this shows an equipment trouble, Sadface Will open it meticulously, wishing I'll locate a damaged follower or something silly like that. Or else, will certainly take it to the store - not eager to mess concerning with equipment despite the fact that it runs out service warranty as the equipment is still worth a reasonable little bit I would certainly claim.

2022-07-25 13:24:56
Source Share
Answers: 7

Speculated diagnosis:

I have seen this happen in quite a few macs since the switch to Intel architecture. Like what some others have suggested, I believe this is 90% most likely the initial stages of hardware failure (your GPU), and is directly related to cooling issues. In my experience, no amount of fresh-installing or hard drive replacing is going to fix this.

It is interesting to note that this is occurring on your NVIDIA hardware, as I have usually only seen the ATI chips fail. The cause behind this could be a flawed/abnormal manufacturing process or could be due to improper heat sink seating or inadequate thermal paste.

Unfortunately, it looks like you are going to be due for a repair soon. Your options there are either to replace the entire logic board (as others have stated, the GPU is soldered on), or have it repaired or "reflowed", a process where the logic board is removed and heated so all the solder melts and re-flows in an attempt to fix any shoddy contacts.

Possible fixes:

There are a couple band-aid type solutions you can try that I have had luck with in the past. Firstly, download a fan control app such as SMCFanControl, and set your fans to run at 100% all the time. It makes the machine noisier, but helps keep your mac cooler and more often under that magic threshold of it going berserk (on my old MBP it was 160F).

The second solution is to take the machine apart and re-apply the thermal paste and re-seat the heatsinks. It can be difficult if you haven't done that type of thing before but it is rewarding when it all comes back together. Obviously if you can afford it, it's best to take it to a repair shop (apple-approved only please!) and have them do it. They should only charge you about an hours' worth of labor and maybe a dollar or so for the drop of thermal paste they use.

2022-07-25 19:22:55

It is fairly most likely that this concern is brought on by equipment (a falling short GPU, more than likely) yet there is an opportunity that it is brought on by software program.

To identify where the trouble exists, boot your computer system right into a tidy install (either Mac OSX/Linux/Windows on a bootable drive, or utilize your "install Mac OS" install disk/partition). If you experience any kind of sort of troubles while making use of a tidy install of any kind of OS, you recognize the trouble is equipment.

You need to run a back-up asap, after that change your GPU (or take it for a fixing). Just effort to fix it on your own if you entirely recognize the guidelines, if you are unclear, a self - fixing might create even more damages

If there are no worry while making use of a tidy OS, the most convenient means to deal with the trouble would certainly be to re-install Mac OSX ; bear in mind to backup your documents first so you do not shed anything.

2022-07-25 18:36:48

Backup is required clearly. First back-up, after that sending it to Apple is advised yet if you do not desire to, you can disassemble it on your own. Tidy it, and also most notably, you require to obtain the ram and also placed it back in, the very same with the warmth sink covering your cpus. The trouble needs to exist with overheat and also unpredictable ram.

2022-07-25 18:36:37

Backup first! Replicate all your crucial documents, and also make a Time Machine back-up when possible.

It can be concerning software program or equipment, it is tough to claim.

I would certainly first advise developing a new customer account and also attempt there.

After that, reset and also and also attempt if that aid.

The last excellent remedy is and also cleansing cache with applications like or .

The negative remedy is simply mounting Mountain Lion on the very same dividing without cleansing your old system. If that does not function, update to Mavericks and also attempt. If that still does not function, you could require to do a tidy install.

[EDIT: You can additionally simply install to an exterior drive.]

Please bear in mind to backup your Mountain Lion installment application when possible, or you could require to locate is elsewhere later on.

If all those over does not function, you could need to send it in for fixing.

EDIT: Try BootCamp and also run a benchmarking device which presses your CPU and/or GPU to the restriction. That will certainly show if it is an equipment trouble.

UPDATE: Check out this , there is evidently individuals having trouble like your own.

There is additionally a to examining your memory, something you can do if you intend to.

2022-07-25 18:25:07

It is your visuals cards. Attempt upgrading them. .

OS X 10.9 is just seen with this problem. Additionally, download and install Adobe Player 11 or 12 beta. There could be an alternative at

Also, make use of Safari or install Firefox, they are called the fastest.

2022-07-25 18:22:52

Installing the system from square one isn't the most effective instance. What I would certainly advise is if you have an extra exterior drive. Offer it a dividing of 25 GB approximately and also install an OS on it. Do not move any kind of files right into the new OS on the exterior. Rather you can open numerous applications (Grapher.app) and also attempt to burn out the GPU and also CPU via an exterior system. If the concern returns after that you are considering more than likely a GPU/video card concern some uncommon instances MLB.

If the concerns do not show up after that you more than likely have a software program concern or damaged HD. If you have the DVDs that featured your mac after that putting the disk that has the Apple Hardware Test (it is published on the disc) and also boot the computer system holding D. This will certainly boot the iMac right into Apple Hardware Tests and also you can execute an extensive examination series.

Even worse instance you attempt an exterior system or AHT and also the computer system ices up or damages the video clip. Any Kind Of AASP or Apple Store has extra diagnostics devices to aid repair. Be warned/advised There is a restriction to how much time a device is qualified for solution and also how much time components are readily available so if the iMac deserves a couple of hundred dollars take it in to get examined and also dealt with. Prior to entering however, please have a back-up all the files you require. I have more than 6 years experience as Apple Certified Mac Technician so if you require any kind of more explanation please allow me recognize. I am being quick yet as exact as feasible to see to it you throw away as little time as feasible.

2022-07-25 17:57:28

I have this trouble with my really comparable iMac, which is why I'm . I can not supply excellent information, I'm rather particular it is an equipment trouble and also the solution is to change or fix the card. For me that really did not appear worth the initiative, offered what I perform with it so I'm making it an ssh web server and also have actually acquired a souped up mini to be my GUI workstation.

I attempted a lot of the workarounds recommended below. Starting in secure setting, trouble still there. Running the follower at broadband, no adjustment. Fresh OS install, still there.

The only point that ever before appeared to make any kind of distinction, and also not nearly enough to be any kind of actual distinction was that if I drew the power cable and also allow it rest for a while, the next time I started the quantity of time prior to the problems appeared a bit much longer.

Every little thing I've read recommends that the trouble is with solder someplace in the system. It was inadequately used to begin with and also damage of heating & cooling has actually made it half-cracked.

Do you get mistakes in your console logs concerning troubles with GL?

2022-07-25 17:53:08