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OSX Lion, Graphic Artifacts

Hello, after i've installed OSX Lion on my iMac 2011 27°, i started getting strange graphical artifacts on my desktop as you can see in this screenshot. http://t.co/5EXmRfL

The graphic artifacts randomly appears, without that i am doing nothing in particular.


Is this a common issue? It's a Lion issue (fixable with an update) or should i format my iMac?

iMac, Mac OS X (10.7)

Posted on Jul 22, 2011 7:03 AM

Reply
394 replies

Aug 3, 2012 12:42 AM in response to Anke

I've had my 27" i7 iMac for a year now and every now and again the screen darts to one side and enlargens everything at the same time. Going to View then down to Actual Size re-establishes the normal screen view. I got fed up with trying to get the fault rectified and it is not too serious a problem, happening most times when using Safari, and hasn't happened for the past six months in FCPX. If it did, I'd have to have it seen to by Apple - MORE CASH!


I'm wondering about replacing the Lion OS with Mouintain Lion but am fearful that it will start more serioius problems all over again . . .

Aug 6, 2012 7:07 PM in response to Hakko83

Hi Andrew,


Well, I'll be trying your flash solution tomorrow when I get my copy of Windows to install from a friend.


I've re-partioned my drive and am ready to go into Bootcamp land.


I'll report back when done tomorrow night.


So the final two quick questions...


Is your flash solution still working for you?

Are you running Mountain Lion yet?


Thanks,

A

Aug 8, 2012 7:11 AM in response to Hakko83

Well I wish I had better news, but I do not.


Andrew, your fix did not work for me. Followed it to the letter, re-loaded the bios to make sure the new settings were there etc.


So, I'm back to running with extensions off now, the only way the machine can run for more than a few mins, and will take it in to Apple and see what they have to say about it.


What a pain.


I've been a Mac user since Lisa, owned and maintained dozenens of Mac networks. This iMac is the first one that's ever given me trouble and the sad part about it is that I'm pretty convinced that its driver related.


sigh


Just for fun Andrew (I'm stubbourn), can you post a screenshot of your bios?

Aug 8, 2012 2:25 PM in response to AA63

I don't have a screenshot of the BIOS, but is your GPU an ATI HD 4XXX or 5XXX card? As I said in my original post, the BIOS fix is a specific fix for a specific problem. It may be that your card is suffering from a different problem.

And I think you're right about the graphics drivers - I'm also convinced that the majority of people's problems stem from poor graphics drivers. People who have upgraded to Mountain Lion are also seeing graphics glitches on variou systems - glitches that didn't exist before.

Aug 9, 2012 8:18 AM in response to Andrew Humphreys

Hi, I'm back. As I mentioned I'm stubbourn.


The reason people are seeing issues now is that Lion/ML (through its drivers) are calling on the GPU more heavily. A lot more smooth scrolling/animation, etc. In my case it was happening in SL as well.


Andew, I went and poured through all of the links that you provided in your fix to see if I could glean anything more. And I think I did. I read everything. Then read everything associated with the tools for the bios adjustments and flashes to get a better understanding of what I was attempting. Here's what I came up with...


The most prominant/consistent theory and observations reported, was that this card "jumps" modes trying to save resources (ram/energy) by clocking itself down. And it is durning these jumps where things get out of sync with the drivers causing the card to cycle and resync itself. This was the cause of the artifacts, and eventually a communication loop between the driver/card each trying to re-sync that lead to crashes.


In my observations, on my machine, this happens in both directions - when it is idle/low use then needs to ramp up (for example when a window opens it needs to call animation) and then the reverse, when it is in high mode (playing a video) and then goes quiet (switching to typing text in Mail for example).


So it occured to me to try something.


I went back into the RBE editor. It shows 4 modes there for the various states (reg, power saving, etc.) that are editable. Two were similar, two different.


So I adjusted the settings and made the first three 00, 01, 02 all the same 698/1000 which was what the 00 default was. The last one was similar but not exact. I flashed and saved and rebooted.


And so, guess what?


For the first time in months, I've been up and running for 24hrs. without a crash. Very stable.


Not perfect yet though. I am still getting the occational grey squares but they are predictable - I can make them happen by switching from what I callied low to high use above. And I can clear them by switching to the dashboard or changing spaces.


So what I'm going to do is continue to test my theory.


First I will use the maching for the day and cycle it on/off to a few times to make sure that this is not an anomoly that it is running smoothly, then finally I will go back into the RBE and make that last setting the same as all the others. From there if it clears up the artifacts I will be good, or at the very least I can then try to play with the settings globally (the same everywhere) and see if I can get the clocking to behave. The only inconsistency would be that second setting 01 where the voltage setting is different from the other three (all are at 1.0 except that one which is 0.9), I'm not comfortable changing that one yet until I know more.


For sake of completeness, the temperature in the machine is relatively the same, no major increase in heat, just a few degrees.

I will report back later.


A

Aug 12, 2012 10:54 AM in response to AA63

Well I'm back with no good news.


I've tried all combinations and can report that none of them have been stable for me for more than a day.


I will try a few other combinations, but honestly I do not expect much. My machine will go in to Apple for a some new parts tomorrow if nothing gives.


A

OSX Lion, Graphic Artifacts

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