Apple Event: May 7th at 7 am PT

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Level 1

0 points

2009 Early iMac Freezing 2.93GHz,24", ATI 4850

I just took delivery of my new iMac 2 days ago.

It's a 2009 2.93GHz, 24" iMac, 4GB RAM with ATI Radeon 4850.

As usual when I take a new delivery, perform a hardware test using the test diagnostic DVD that came with it, checks out fine.

Next, erase the HD and reinstall 10.5.6 from the supplied DVD, applied the updates, then use Disk Utility to check the HD and repair permission, no problems, then after a couple of minutes, the iMac froze. I have nothing connected except for the keyboard and mouse.

Mouse does not move, keyboard does not respond to input. Pressed the power button for 5 secs to shutdown. Booted up in single user mode to repair HD, started up fine again, started to install my apps and move the files over from my previous iMac. Played movies on it, and it froze again. Mouse & keyboard does not respond to input, just a short 1 sec sound from the movie that kept looping.

This happens a few times a day.

Got fed up, reinstalled the OS again, zapped NVRAM, PRAM, Disk Utilities check, repaired permissions, started to play COD4, just a couple of mins into the game, the iMac froze again. Keyboard & mouse will not respond to input, sound stutters.

What's wrong? Any ideas?

2009 Early iMac 2.93GHz, 24" ATI 4850, Mac OS X (10.5.6)

Posted on Apr 15, 2009 11:16 AM

163 replies

jjdombro

Level 1

0 points

Apr 16, 2009 8:01 AM in response to Nic T

I experienced the same issue. Did not even get through the initial setup (got to the point where it was asking me if I wanted to transfer files from old mac and it froze). Tech support told me only thing to do was to turn it off. Did that, and came back up and made it thru setup process (no file transfers). BUT...about 2 minutes into looking thru finder - FROZE UP AGAIN. Tech said may need to reinstall OS...did that as well...re-setup and it did the same thing within 5 minutes of using NO SOFTWARE AT ALL!!!

Called this morning and they are sending me ship back instructions and are building me a new one (hopefully that works this time). The rub is that it is a 5-7 day build time again...no way around it they said.

Once I described problem and what I did they were very receptive to the new machine idea I insisted upon. I guess that is the good news.

Nic T Author

Level 1

0 points

Apr 16, 2009 8:23 AM in response to jjdombro

Good for you. Let me know if your replacement fixes the issue.

I'll keep everyone posted as well when I get mine.

Apr 18, 2009 12:08 AM in response to Nic T

I'm having the same problem and I didn't use the migration assistant (copied over some of my data manually). Just got the machine today and it has crashed twice already. Not sure what the problem is as I have a lot of things open at once but often there is a video open in the browser. I am wondering if has to do with the ATI drivers and Flash 10? Computer just freezes and the sound starts stuttering. Don't get the pretty screen of death or anything like it but have to restart

Nic T Author

Level 1

0 points

Apr 18, 2009 7:33 AM in response to Ben Skelton

You can rule out Flash 10, mine was a clean install and it still froze. I hope these are isolated cases. I'm gonna get my replacement next week, and it'll be a real pain to have to send it back again.

Nic T Author

Level 1

0 points

Apr 19, 2009 12:08 AM in response to Nic T

AppleInsider is running a story on this, they referred to this thread and the other.

http://www.appleinsider.com/articles/09/04/18/newimac_owners_see_radeon_hd_4850_related_lock_upissue.html

Some new information from AppleInsider.

+Some of those calling the company's support line have heard from technicians that there are numerous reports and that a fix is in the works, possibly arriving along with the looming Mac OS X 10.5.7 update.+

Apr 19, 2009 4:17 AM in response to Nic T

Aw, man I was bummed to see this in Appleinsider this morning!

I just received my 2.93Ghz iMac with ATI 4850 card this week. So far, no problems, but I haven't had a chance to use it much or stress test it yet, as I've been away for work.

I love my new Mac and will cry if it starts freezing!

Nic T Author

Level 1

0 points

Apr 19, 2009 4:47 AM in response to Martin Spencer

Let us know if it freezes on ya.

Apr 19, 2009 4:48 AM in response to Nic T

Wow, am I ever happy that I saw this forum thread. I hadn't yet tried watching HD video...

I've got the SAME problem and it is highly repeatable. Just watching an HD movie trailer, the iMac freezes within about a minute of video.

Argh! I'm going to get on the phone to Apple... I will keep everyone posted.

Apr 19, 2009 5:52 AM in response to Martin Spencer

OK - so I reset the NVRAM and PRAM, and now I can't repeat the freezing... I am so concerned that something may be wrong - and now that I can't repeat the issue, I'm double-concerned that I won't get any support for it.

...I guess I just have to wait for Apple phone support to open up.

Apr 19, 2009 5:13 PM in response to Martin Spencer

So I am able to repeat the issue at will, each time by playing 1080p HD video through Quicktime.

I phone Apple phone support today and will be shipped a replacement iMac. They won't ship my replacement until there's a shipment confirmation that I'm sending them back my current computer, however, so I expect to be out of a Mac for another month.

...very frustrating!

Apr 19, 2009 5:15 PM in response to Martin Spencer

...also - based on advice in the 3.06ghz thread on the same topic, I've installed Fan Control for Intel iMacs, and am hoping that will keep things at bay until the replacement iMac comes (along with a firmware update from Apple along the way, I'm sure).

Apr 19, 2009 6:24 PM in response to Nic T

Add another to the list.

2.93ghz, 640gb HDD, ATI Radeon HD 4850

Froze 2 times on the first day without any intensive processes. Opened my entire applications folder at once, ran 5 videos at a time for an hour, no freezes. Browsing in Firefox and listening to iTunes and it locks up. Calling Apple on Monday for a replacement, hopefully the new ones going out have had the problems fixed, and Apple isn't just hoping that they'll work.

HutchD

Level 1

0 points

Apr 19, 2009 10:12 PM in response to open0source

Add me to the list.

Had the machine for no more than 2 days and I received multiple freezes. First one was during initial time machine transfer... the last dozen have been occurring at random in 10.5.6 and XP pro under bootcamp.

Called and talked to Apple. On the phone they tried to have me replicate the freeze, and for a good hour it wouldn't... go figure. Not sure where to go from here but I think I'll be calling back now that they should know it is a widespread issue with the ATI 4850s

Nic T Author

Level 1

0 points

Apr 20, 2009 12:10 AM in response to Nic T

Does anyone have a 2009 Early iMac with the 4850 that does not freeze?

Sermon

Level 1

9 points

Apr 20, 2009 12:33 AM in response to Nic T

I've had mine since April 14 and haven't experienced one single freeze or lock-up yet. Which of course doesn't mean that my machine is freeze-free.

2009 Early iMac Freezing 2.93GHz,24", ATI 4850