OSX Lion + 2011 iMac 27'' + Video = Freeze

fvd,

The first Genius was not very nice saying it was my memory, started saying you have 3rd party memory. I looked at him and laughed and said I guess Apple is buying 3rd party memory as I bought the unit from you guys and its your memory installed. Then it was the hard drive, then the logic board, all because of Lion, yes I said he here! I was orginally told to upgrade to Lion because of the glitchy version of Snow Lepoard and the rest is history. I wouldn't be suprised if in the next 3-6 months we see a class action because of this. Big companies in order to stear clear of a big problem, is to take care of it quickly, since Apple builds everything in China, you would think they would keep some manufacturing jobs here, then I could understand the higher prices. 😉 But they just will have higher profit margins.

In your case it was even funny. As for me... Well I guess if we dont see anything changing here my next computer is going to be Asustek.

UII or one of these:

http://reviews.cnet.com/desktops/vizio-ca24-all-in/4505-3118_7-35331605.html?tag =mncol;txt

Still not up to the specs of iMac but at half the cost it might not be a bad option.

I formatted from Lion and went back to a clean install of 10.6.8 for a test way back, soon after I first had the issue. It didn't help.

I'm back on Lion.

Hoping for what I feel is a graphics card firmware update from Apple, and not doing the PC work around for this card, for now.

The machine was as stable as a rock running 24/7 use/sleep for more than a year before the black screens and top left rear case overheating started. Just after an Apple firmware update, about lion 10.7.3.

I hope that we can get Apple to look at this, and give us some stability.

My 2006 Asustek is still "Heart touching, Rock solid" (their motto)

You have actually nailed it down for me. I have experienced the problems since 10.7.3. Going back doesn't fix it.

I had the faulty MBP silver keyed 2.4 that was repaired out of warranty for graphics blackout.

I also still have a Powerbook G4 1.67 in the drawer from this problem. That was a thorn in Apple side when they denied it for so long:

http://macdailynews.com/2008/11/03/apple_sued_over_alleged_defective_powerbook_g 4_memory_slots/

I hope this gets fixed. I can't use my machine fully until it is.

I was having a ton of problems in Lion with my iMac but I also discovered that I had installed some faulty RAM. After taking out the RAM, I did a clean install of Snow Leopard and haven't upgraded to 10.6.8. I happy to say that after purchasing some quality RAM and not updating my machine, it is running perfectly at 10.6.6.

(I have a late 2009 iMac 27" with 16 gigs of RAM)

is there a way to check faluty RAM?

i think my problem might have started after I added 8 GB (purchased from RamJet)

Yes, through an Apple Hardware Stress Test. This is easy to do, and hopefully someone will give you the details here. I had the test done for me at the genius bar. My problem was, in the end, that I did not insert the added memory exactly perfectly.

Same black screen/still running problem on a 27" iMac10,1 Late 2009 Core2Duo 3.06 GHz > OSX10.6.8 < HD4570 card

The problem is not restricted to Lion, Lion has never been installed

Machine has been in to an AASP twice, no fault found

Apple firmware is up to date

10.6.8 v1.1 Combo updater has been installed

SMC Fan Control is on, fans are cranking, temp is 31 degrees and it still blanks. It is not heat (or at least not primarily heat)

The Control Shift Eject then space bar routine does work, often for only 3 seconds though

Oddly, it ran for 4 days with no trouble when offline (no Airport, no cabled Ethernet) and blanked the screen within seconds of being plugged in with an Ethernet cable

My mid 2010 iMac has the same problem as yours even I reverted to SL. I'm really mad with this.

Someone on here suggested contacting Apple executives and put a link to an email. That message promptly vanished, but not before I sent a polite and informative mail with links to here off on its way.

I got a prompt reply saying that they will contact me, which they did.

They said they were unaware of the problem.

But, that said, would have a top tech remote in to my machine to have a look, and take information from me as to what the problem is.

She also said that Apple execs do not read this site.

I will push this through hopefully to a solution.

I think another angle of approach is necessary other than talking about it amongs ourselves on the gated Apple forums.

I felt positive about this call. They honestly sounded more helpful than anyone at an Apple store.

I've noticed a trend lately with our machines. They only go black in the morning when first on, once they warm up, it won't go off all day. We're lucky that the shift+control+eject, then space bar gets them right back, but some mornings it will take 15-20 of those before the machines stable out.

this leads me to believe that something could be loose and when internal temps get hot, things expand and the connection is good. I may open it this weekend and look around, disconnect/reconnect all including ram and see if that helps

Just to further put forward Andrew Humphreys' solution on page 120 of this thread:

I've just spent a substantial period of time doing what Andrew suggested, i.e. installing Boot Camp (which in my case involved erasing my HD for some reason), installing Windows, updating the various versions of Boot Camp on the Windows side from 3.0 to 3.3, and then doing the GPU Flash thing using the utilities he mentioned.

Took me about 5 hours but it seems to have solved the problem!

I was even getting corruption on the Windows side of things as per the Mac side. And my corruption on the Mac side was getting progressively worse week by week. It was getting to the stage that anything remotely graphics intensive (or even not) was resulting in graphics corruption and then the thing would hang. The corruption would start pretty much from startup. In the worst cases, the screen would go black.

It definitely is a hardware issue that has been solved by adjusting the GPU settings on the graphics card. I don't use Lion (just Snow Leopard) so it's not that.

Hopefully Apple takes note and can offer a solution that doesn't take substantial mucking around as what I've gone through. But at least Andrew's solution does work. Thanks Andrew!