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AppleGirl1990 · Apr 18, 2009, 04:21 PM

I just saw on AppleInsider that some new iMac owners using a Radeon HD 4850 are having lock-up issues. I am considering ordering an iMac with this graphics card (as a 2nd computer), but i'm now thinking of holding off.

Can anyone who has this latest graphics card comment on it's performance and it's stability???

AppleGirl1990 · 10:02 AM

that doesn't exactly help answer my question...

The spam post you're referring to has been deleted with extreme prejudice... Glenn

CharlesS · Apr 19, 2009, 02:05 PM

Order something else. I don't have experience with that particular graphics card, but I do have a MBP with another card that has lockup issues (the NVidia 8600M), and it's incredibly irritating to have to hard reboot your machine 1-2 times a day.

Of course, if Apple would ever bother to put proper cooling into their machines, this wouldn't be an issue. But apparently a little extra thinness (in a desktop, where it provides no advantage) and a little less fan noise is a bigger priority than a $2000 machine actually working right.

AppleGirl1990 · Apr 21, 2009, 07:27 AM

http://forums.macrumors.com/showthre...=688393&page=5

The leading theory at the moment is that WiFi is causing the crash.

Simon · Apr 21, 2009, 07:36 AM

IIRC some of the first Al iMacs had a similar problem. Apple eventually fixed it with a firmware update.

CharlesS · Apr 21, 2009, 12:45 PM

"Eventually" being the operating word here. I understand that they had to put up with the crashes for a long time.

Seriously, putting up with constant crashing is not worth a slightly faster frame rate. Remember, your frame rate is 0 FPS when the computer is locked up.

Simon · Apr 21, 2009, 01:07 PM

Yeah, I agree, but we really don't have many details to make proper judgement so far.

CharlesS · Apr 21, 2009, 01:25 PM

Well, we have Apple's past history. With the original aluminum iMac, it took them about three months to release a fix, and then many users reported that the fix didn't completely resolve the problem for them. With the NVidia 8600M in the MBP, they took about seven months to acknowledge the issue and set up a recall program, and I know that replacing the motherboard on my MBP didn't fix that one at all. So what we can assume based on history is that 1) the fix will take an amount of time that you can measure in months, and 2) when Apple does address the issue, it's not guaranteed that it'll actually fix anything.

AppleGirl1990 · Apr 21, 2009, 07:42 PM

well, if it's only with that specific graphics card....then i assume it's safe to order the new iMac with the factory graphics card?

Simon · 03:14 AM

As I tried to point out above, I think so far the problem hasn't even been established yet. Right now we don't know if just one or all 4850s are failing. Are they actually failing at all? Or is it a software issue? Is the problem widespread? Does it require certain software settings/configurations? There are simply not enough details available to answer the question right now.

AppleGirl1990 · Apr 22, 2009, 07:34 AM

Based on the hundreds of responses, its safe to assume it's not just happening to 1 person.

Simon · Apr 22, 2009, 08:40 AM

But is it happening to everybody? And under any circumstances or under special circumstances?

boy8cookie · Apr 22, 2009, 04:28 PM

It's nothing to do with any software being installed, as the machine has been reported to freeze, right out of the box.

There are several theories that the graphics card is overheating in some machines, the fans are not spinning at all, and installing a third party controller for the fans has been said to resolve the issue.

I've been reading every forum about this particular problem, I was hoping to purchase this machine, but I'm glad I waited to see its performance.

AppleGirl1990 · Apr 22, 2009, 05:43 PM

BoyCookie, i still want to purchase an iMac like you. But wouldn't you say it's safe to purchase an iMac with the out-of-the-box graphics card, i.e., NVIDIA GeForce GT 130 512MB ?

No freezes with this graphics card right?

boy8cookie · Apr 23, 2009, 02:47 AM

A machine with that graphics card should be fine to purchase.

AppleGirl1990 · Apr 27, 2009, 07:22 AM

Despite everything said, i decided to hold off on an iMac purchase for 2 months. Hopefully everything is figured out by then.

Simon · 03:15 AM

I think that's not a bad idea, if you can wait.

We don't know for certain yet that the 4850 causes problems for everybody. If you go for it now and end up in trouble that would suck. OTOH if there's a fix for the 4850 issues some people are seeing and you go for the 130 now, you will always regret not having bought the faster GPU.

Waiting now means you'll be making an informed decision once the details are known.

boy8cookie · Apr 28, 2009, 01:37 AM

Actually, 100% of users (who post) with 4850 and airport enabled are experiencing freezes. People with the 4850 card and airport turned off (using ethernet for internet) are experiencing no freezes. The problem is exposed, a conflict between the airport card and the 4850, now we can hope for a resolution.

Simon · Apr 28, 2009, 02:52 AM

http://www.macfixit.com/article.php?...90421093609492
http://forums.macrumors.com/showthread.php?t=688393

olePigeon · Apr 28, 2009, 01:02 PM

Windows XP freezes on my MacBook Pro when the wireless is turned on. I wonder if it's related.

smoak5 · May 2, 2009, 03:39 PM

new update through software update to address this problem is up.

Simon · May 3, 2009, 03:12 AM

Apple releases iMac EFI firmware update to fix Radeon HD 4850 issue

http://support.apple.com/downloads/_...are_Update_1_4

AppleGirl1990 · May 3, 2009, 05:04 PM

Apple today released an iMac Firmware Update 1.4 to resolve some outstanding issues with certain models freezing and another issue with Bootcamp, Apple's technology for allowing users to run Windows on Mac. According to Apple's documentation, the update fixes intermittent system freeze issues for iMac computers with ATI Radeon HD 4850 graphics and fixes wake-from-sleep issues in Boot Camp. Readers report that the iMac freezes occur in a wide variety of applications--and even when not running Mac OS X (such as Bootcamp) and that typical troubleshooting steps do not resolve the issue.

axlepin · May 18, 2009, 06:28 PM

so, has this updater solved the problem in iMacs with the 4850? I haven't heard either way in my reading...

a