The artifacts issue have ben solved since I've installed Lion 10.7.2 and I'm using it for 6 days and all is okay.
If after installing the Lion update the artifacts persists, specially on exhausting video task, I recommend checking the video card by booting using another OS, such as Snow Leopard or Windows trhough Bootcamp, and running an exhaustive video task, like playing a video game for a while. That will show up if it's the card or not.
Here is a good link about artifacts on screen related to video card problems: http://www.playtool.com/pages/artifacts/artifacts.html
27" iMac 3.4Ghz Quad Core i7
Radeon 6970 1Gb
Lion Os x 10.7.2
I've been experiencing problems since day one, I bought it a month ago, and there has yet to be a software update that addresses it, I'm beginning to lose my patience.
It's inconveniencing me, and flat out unacceptable.
I paid top dollar for a product that's supposed to be entirely self maintained and fully compatible, and yet I'm having some prominent graphics issues. That either are aesthetically unpleasant, ( on startup, grey apple screen has pixelated lines in square groups, see photo below), or actually counter-productive, such as when I wake it up from sleep mode, it displays small clusters of square discoloured pixels, and freezes the entire system, only to be remedied by restart.
I will be contacting any apple support that's available, and will not rest until I am either compensated for this utter inconvenience and hassle, or they promptly release a software update, or driver update addressing the incompatibility with the graphics card, or it's software.
You can try making a disk partition (your stuff won't be erased) and once done (it takes few hours), installing snow Leopard into there, boot from there and see if you keep having the same video issues. if so, make sure to troubleshot your video card. You can also try boot from Windows, if you have Bootcamp. that way you will know if that's a software problem or a hardware one.
Yes. The OS Emultaros don't stress the video card. You need to test the video card with stressing applications such as video games, benchmark software like Cinebench (to stress the OpenGL features of card if not having a very graphcis demanding video game) in order to see if you're having a hardware problem (mostly, overheating). A simplier thing you can try is booting Lion in safe mode (Shift key when starting up the system). If you find no artifacts, then it's probably that you're experiencing a hardware problem, so you would need to go deeper and do the stress test mentioned above.
I'm saying all this because of my experience, and found that at first instance, I just were having few artifacts, not all the time and not when playing video games but, as the time passed by, the artifacts were more and more frequent, started to be the freezes till the point of being unable to start the Mac up (but in safe mode).
So I was using safe mode for about 5 days, upgraded to Lion 10.7.2 and because of the persistence of the problem, tried the same video card on a Windows machine and yep, my video card was dead. bought an ATI HD 5850 1 GB etc, etc, and all fixed
Hope this helps!
I sincereley hope it's not a broken Gfx Card, like I said this problem has basically been present from day 1.
There is no way I'm spending more money on repairing / replacing a part that they clearly gave to me broken.
I'm currently doing the back and forth on the phone game, with their support. Hopefully they can offer me some sort of guidance.
Honestly that looks like faulty graphics hardware. Have you tried booting to the OS X installation disc or another OS isntallation at all (even Windows via Boot Camp)? If the same problem happens there then this definitely indicates the hardware is malfunctioning. Generally this type of problem happens because of faulty video memory (ie, texture components can be stored but not retrieved from memory, so you get gaps and other corruption), but could be from other faults as well.
I have a similar problem on my trusty old G5. It's a great system, except for the artifact issue that clogs the display and corrupts pretty much any visual process that is accelerated (ie, uses OpenGL).
I have been waiting a while to post again, but ever since upgrading to 10.7.2 on 12/10/2011, the artifacts problem appears to be fixed for me. My iMac is now running as it should :-)
One other thing, I did also run the Apple Hardware Test (http://support.apple.com/kb/ht1509), to check for any hardware problems. I just ran the quick test and all was ok. The longer test takes over an hour. I may still run it at some point but everything seems fine now after upgrading to 10.7.2.
It was a slightly odd procedure for running the test. As the Apple Hardware Test was located on the Applications Install Disc 2 that was included with my computer. I had to insert the disc into the iMac then shut down the iMac with the disc still inside, so I could restart it following the instructions in the http above.
I hope that 10.7.2 has fixed your isuues as well, if not it might be worth running the Apple Hardware Test to see if that throws up anything.
I have a 24inch iMac (Nvidia GT 120 256MB). I know it's not a 2011 but this might help...
SL since release - NO graphic issues. Not one on a machine that runs mostly 24/7
Lion - graphics issues, crashes, freezes 5 times a week. Crash, freeze, have to reboot.
I waited to install 10.7.2 fresh so it's a fine running system. I've noticed if i run apps in full screen, the system crashes quicker (presumiby overheating the graphics card)
Result? This is a Lion issue. Apple, fix this!
Sometimes crash reports are available - i've emailed them all to Apple. Roll on 10.7.3
My Early 2009, 9.1 (Nvidia GT 130 512 MB) has been experiencing locking up while playing WoW beginning about 1 1/2 years ago. It was sporadic at the time. During that time and Snow Leopard, it would do it more often. Yes, of course, I was aware of issues with Snow Leopard and the video card. It would happen maybe once or twice day. I have taken the computer to the Genuis Bar to no avail. I was told there was nothing wrong with my computer. The Apple Hardware test had a clean bill of health after I ran it as well. I upgraded to Lion and the smell of failure was in the air. My system kept locking up multiple times a day. The artifacting began to happen. I wish I had just a small area of it. In Bootcamp, I began getting BSOD (driver issue, nvlddmkm.sys within a minute or two of running a game).
Over the weekend, I ran another Apple Hardware Test, and it reported nothing wrong. Granted, on the reboot, I could see where the extended test ran and was ghosted on my screen. To make matters worse, downloaded a game demo on Steam. Within a minute, yet, another crash. This was done with a clean install of Snow Leopard.
As far as I have seen, Apple has never really addressed the issue. Firmware updates have been released that do not apply to my computer. Installing Lion actually feels as if I pushed the Video card issue further ahead then it needed to be. For the time I have had this computer, it has cost me $ 1000 a year to own. I am almost wondering if Apple will ever actually fix these issues. Buying a new computer is not an option at the moment. Any thoughts?