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Can 4850 iMac owners help find the cause of the freezing? Is it WiFi?

mstam said:
The chipset on the motherboard will be exactly the same. The video card is connected to the PCIe interface of the South Bridge.

If WiFi seems to cause the lock-ups, it might as well be an interrupt issue or the WiFi card and video card are using the same memory address range. It's most likely the video card causing the issues because people w/ nVidia cards don't experience the lock-ups. A firmware update for the ATI 4850 should fix this.

Kind of sloppy Apple didn't find out about this earlier. I was about to get myself the 24" iMac but will wait till the problem is solved.
Click to expand...

You are totally right, man! :)

Just think: When there are two totally identical iMacs but one with ATI and one with NVidia graphics card and the one with the ATI graphics card is crashing, what could be the reason for that? ;)

As it looks like that it's not the driver causing this problem as the iMac also seem to crash under Windows/BootCamp, I also do not think it could be the firmware as one half of all reported iMacs crash, the other half not. Same with Wifi or Bluetooth. If the firmware would be responsible for the crashing, all iMacs with ATI graphics card ought to crash.

I believe that Apple got a batch of (some, not all) faulty graphics cards from ATI. This would also explain why it took so long (compared to the ones with NVidia chip) to deliever the new iMacs with ATI graphics card. Maybe they knew of this problem. First I thought they could be waiting for the 10.5.7 update with new drivers - but all ATI iMacs have 10.5.6. If it's really a matter of a bad batch from ATI then I'm certain that Apple already had some serious words with ATI and they certainly will take care of that never happen again. And from the perspective of an entrepreneur I understand that it's better to wait for the affected customers to return the defective iMacs then to start a massive recall program.

Thank god in heaven that my iMac 3,06/ATI 4850 is not crashing at all. I have it since April 15th and no single crash until that. I have to admit that I did and do regular tasks until now, no stress test with the graphics card or other heavy duty - only installing programs, working with some apps, surfing, writing mails, playing small games, using VMWare with Windows a little bit, watching the latest LOST episode in HD and so on. And it did not crash at all. Maybe I'm lucky, maybe it will occure in future. But if it occurs - I'll certainly wait a little bit before demanding a replacement to prevent getting a defective iMac again. The next batch is certainly error free. Damn early adoptors... ;)
 
I have been using enthernet and have not had any freezing issues. I have however had wifi turned on the hole time as well, just not logged in. I'm now logged in on wifi and I've been watching movies in iTunes and copying about 120gb of backups from a hard drive to a ReadyNAS with no issues so far. Theres 4 hours left on the copy I'll update this post if anything happens.

2 hours left now and no and no problems.

been running with Wifi since last night, no problems at all.
 
My tech support agent says he has had several calls on this but Apple does not know the cause and that is why they want them back. :(

I am waiting for my labels so I can ship it back. Since I have a BTO (8 GB RAM), it will probably be a couple of week to get the replacement. :mad:
 
cwscws said:
I believe that Apple got a batch of (some, not all) faulty graphics cards from ATI. This would also explain why it took so long (compared to the ones with NVidia chip) to deliever the new iMacs with ATI graphics card. Maybe they knew of this problem. First I thought they could be waiting for the 10.5.7 update with new drivers - but all ATI iMacs have 10.5.6. If it's really a matter of a bad batch from ATI then I'm certain that Apple already had some serious words with ATI and they certainly will take care of that never happen again. And from the perspective of an entrepreneur I understand that it's better to wait for the affected customers to return the defective iMacs then to start a massive recall program.
Click to expand...

I agree, there being a batch of faulty cards seems by far to be the most likely culprit. If the Wi-Fi was the issue then everyone using Wi-Fi would have issues, but several people have reported no crashes under Wi-Fi and several others have reported they DO get crashes under Ethernet.
 
adding RAm to 4850 iMac

So I'm waiting for my 3.06 iMac, presently "prepared for shipping". Anxious about the freezing problem, but also concerned about adding memory. My plan was to get an 8GB kit of third party RAM, but if I'm dealing with a problematic computer & Apple service, I can't add the RAM! This should not be that difficult. Upside: people receiving iMacs in the last 24 hours don't seem to be having the freezing problem as far as I can tell.
 
I saw a post on Apple Discussions in a thread about freezing iMac with ATI 4850.
Nic T said he just received his replacement, and he posted some hardware infos. I just checked mine,
and the only difference I see is the AirPort Firmware version. His is 5.10.38.25, and mine is 5.10.38.27.
No freeze for him so far. I am wondering if it is really wifi... :confused:

If anyone with an early 2009 iMac with any Nvidia chip, would you please check your AirPort firmware version?
 
DELTAsnake said:
Your firmware is the same version as mine and I've had no problems. My guess is that whatever is causing it dosn't cause a problem for everyone. Just luck I guess.
Click to expand...

I guess I will accept that now, I am too tired of testing for what Apple should have done before release it. :(
 
GamaFu said:
I saw a post on Apple Discussions in a thread about freezing iMac with ATI 4850.
I just checked mine,
and the only difference I see is the AirPort Firmware version. His is 5.10.38.25, and mine is 5.10.38.27.
No freeze for him so far. I am wondering if it is really wifi... :confused:
Click to expand...

5.10.38.25 is just the normal firmwareversion without the latest airport security update. When my last replacement arrived I tried not to install any updates but it crashed anyway ... with 5.10.38.25.
 
Headliner said:
sounds far fetched... but then who knows? this just keeps getting weirder lol. Can we debunk this one right away? Know anyone with a working 1TB machine?
Click to expand...

I have a 1TB machine, 3.06GHz, 4850, and it is working. I also tried hooking it to wifi, been running for 2 days, no problems. So now i've been running almost 2 weeks no freezes.
 
Just thought I would let you know that on my first day towards the end of the night I was playing 3 songs on my itunes with the visualizer full screen on my iMac 3.06 Ghz , 4850 ATI Video and on the 3rd or 4th song, it froze. :( I was disappointed to say the least. I been reading some here on this thread and some of you think it is the WiFi that is causing the problem. Well I was using WiFi so I turned it off and now using Ethernet cable and went into my itunes and played songs for 90 minutes with the visualizer full screen for over 90 minutes and IT DID NOT FREEZE. No problems so far since i disconnected the Wifi. :D

So is it possible that this could be the reason why the lock-ups? I will continue to monitor the situation and if it changes I will let you know.
 
I posted this in the other thread but it applies here too.

Got my iMac this evening. Just to add my two cents:

Initial setup of the iMac went fine, using wifi to do the registration stuff. I downloaded and watched a couple of quicktime trailers in HD. Worked just fine and the iMac's screen is beautiful. Downloaded and used "Teleport" which allows me to use my iMac's mouse and keyboard to control the Power Mac G4 that's sitting right next to it, over the network (via wifi). It worked fine.

But then I installed and ran Halo 1 (v2.0.3). It froze during the opening cinematic (conversation between Cortana and Captain Keyes). I restarted and opened Halo again. It froze again during the first playable area where you're learning the movement controls. I then turned wifi off and ran Halo for the third time.

With wifi off I was able to get through the whole first mission with no freezes. That kind of tells me personally that it's the wifi, but something else needs to run to be the catalyst for freezing. Regular web usage didn't do that for me, nor did watching some videos. But the clear difference between being able to run Halo and not being able to run Halo for any appreciable amount of time was the wifi.

EDIT: It just froze again while watching an HD Youtube video. On wifi.

Take that how you will: another data point.
 
I own 1 Freezing iMac:

Arrived on 4 days ago on 20th April. Frozen 4 times (once was bluetooth mouse issue) mostly in safari once in mail(!!!). Have not yet pushed GPU in 3D app and have not yet been sucked into WoW.

24"/3.06Ghz/1TB/4GB/ATi 4850!/wired keyboard/wireless mouse/using WiFi

Factory: W8 (Shanghai China)
Production year: 2009
Production week: 15 (April)

This is a really interesting thread, i hope people keep posting! so far all the freezing macs that have posted fact. details were production wk 15th April? is that right? That would point to faulty batch of cards surely....??

If it turned out to be a WiFi problem, is that likely to fixable with firmware/software solution? I have a ordered a replacement which i was told would arrive in a week or so.:mad:

NB: I also had to endure the delay for my iMac - I reckon apple have known about this for a while whatever it is.

I also get a value of 3.60Ghz in the Apple Hardware Test...
 
new infos from user Nic T (Apple Discussions)..
I've been using my replacement for the whole day now, Airport is on, played 3 HD movies in loops at once, played COD4 not a single hiccup.

Woohoo, problem solved.
Click to expand...
Crap, spoke too soon, was playing COD4 and it froze on me again, same symptoms. What a bummer.
Click to expand...
seems the replacements aren't any better :(
 
If my first replacement freezes, I am calling for a second one immediately. I will play their game all summer long.
 
Poisednoise said:
Crashing iMac with wifi, so far no crashes without wifi:

Wireless Card Type: AirPort Extreme (0x14E4, 0x8E)
Wireless Card Locale: Worldwide
Wireless Card Firmware Version: Broadcom BCM43xx 1.0 (5.10.38.27)
Current Wireless Network: AirPort is currently turned off
Click to expand...

Hi all,
since last saturday I got 4850 based 24 imac. Lots of freeze, I started using Wifi heavily. Then used fan control, it froze anyway.
Then disabled wifi, no more freeze.
My revision of Wifi is the same as Poisednoise.

If you have a look on airport utility ->Advanced -> Log and Statistic -> Wireless clients -> Wireless clients -> my iMAC Wifi has peaks of -20 dB with average of -65dB, while my MBA is stable to -60dB.
May be all these peaks overheat overall system, even ATI GPU, if I am in the unlike situation I got a graphics card mounting a "thermal corner lot" core.
I am keep trying to understand if:
- wait for a sw fix
- wait for Apple admitting something (HW) needs to be changed.

I think it is not possible to point a finger to a card ( either Wifi or GPU): it is an integration issue not well analyzed before shipping new iMAC.
Apple, this above is wondering me a lot.
Bye.

:apple:MBA 1.6Ghz, :apple:iPhone 2G 8Gb :apple:iMac 24'' 1TB 3Ghz ATI4850
 
I got my new iMac yesterday (3.06 with the 4850) and set it up last night. It froze repeatedly on startup while playing the "welcome to apple" ditty. Bummer. I called the help line and we did a quick test - since then, everything has been just fine without any freezing at all so far in several hours of uptime. I'm keeping my fingers crossed.

What we did:

I was asked to hold down the shift key while starting the computer because I couldn't even get it to load up the OS intially due to my early freezing. This put the computer in safe mode. Under programs/utilities there was a disk utility that I was asked to run (need to go back and get the exact name). One option near the bottom of the opening menu had me do a scan of current software against a database of stored software values. The test took 5-8 minutes to run.

When completed, the message said that some file in iLife wasn't correct and it replaced it. The tech guy on the phone said that sometimes when they do mass installs a file could get corrupted (true or untrue, I have no idea since I'm not a techie). They said that this test/repair that I did should fix it.

I restarted the computer like normal after that and everything has been working just fine so far. I proceeded to use migration assistant (2.5 hours), surfed the web, downloaded and watched a dozen movie previews from the Apple website, logged in and played wow for about 30 mins on "ultra" setting...and all is still well. I'll note that all of this was done over a wireless connection as I haven't disconnected the hardwire network cable from my "old" iMac yet due to the freezing fears.

I don't have enough time spent using the new iMac to tell whether or not my machine is "cured". The limited results so far though are promising. Could it really just be a corrupted software file in iLife that caused the screen freezing? It seems far fetched but, whatever, the proof so far is in the playing. If my machine locks up again, I'll post here.
 
SiliBear said:
I don't have enough time spent using the new iMac to tell whether or not my machine is "cured". The limited results so far though are promising. Could it really just be a corrupted software file in iLife that caused the screen freezing? It seems far fetched but, whatever, the proof so far is in the playing. If my machine locks up again, I'll post here.
Click to expand...

It seems pretty unlikely, but I really, really hope this is the culprit. Thanks SiliBear.
 
SiliBear said:
I got my new iMac yesterday (3.06 with the 4850) and set it up last night. It froze repeatedly on startup while playing the "welcome to apple" ditty. Bummer. I called the help line and we did a quick test - since then, everything has been just fine without any freezing at all so far in several hours of uptime. I'm keeping my fingers crossed.

What we did:

I was asked to hold down the shift key while starting the computer because I couldn't even get it to load up the OS intially due to my early freezing. This put the computer in safe mode. Under programs/utilities there was a disk utility that I was asked to run (need to go back and get the exact name). One option near the bottom of the opening menu had me do a scan of current software against a database of stored software values. The test took 5-8 minutes to run.

When completed, the message said that some file in iLife wasn't correct and it replaced it. The tech guy on the phone said that sometimes when they do mass installs a file could get corrupted (true or untrue, I have no idea since I'm not a techie). They said that this test/repair that I did should fix it.

I restarted the computer like normal after that and everything has been working just fine so far. I proceeded to use migration assistant (2.5 hours), surfed the web, downloaded and watched a dozen movie previews from the Apple website, logged in and played wow for about 30 mins on "ultra" setting...and all is still well. I'll note that all of this was done over a wireless connection as I haven't disconnected the hardwire network cable from my "old" iMac yet due to the freezing fears.

I don't have enough time spent using the new iMac to tell whether or not my machine is "cured". The limited results so far though are promising. Could it really just be a corrupted software file in iLife that caused the screen freezing? It seems far fetched but, whatever, the proof so far is in the playing. If my machine locks up again, I'll post here.
Click to expand...

SiliBear, I have run disk utility from the Applications/Utility but I cannot find the option near the bottom of the opening menu to do the scan of current software you are mentioning. Can you give more details, please?
 
After reading this and other threads about 4850 Imac's I am really starting to believe that all of the new Imacs with Ati card have freezing problems, but only people who are using wifi know it and experience it.
 
I just found my personal culprit, I doubt that it will work for a lot of people:
I had my iBook connected to the iMac via FireWire through the FireWire hub of my external hard drive and it'd crash within minutes of booting the iMac. But the iMac just ran three hours without a freeze without the iBook connected. Then I plugged in the iBook again to test => iMac froze within five seconds.

Not sure though if it's the iBook's, iMac's, the external hard drive's or some cable's fault.
 
Well, i am also suffering freeze-ups on mine with the airport enabled.

Received my iMac yesterday, when it first froze up when I was importing and arranging photo's with iPhoto.

Tonight I watched 3 HD trailers from the apple site this evening through wifi. 2 out of 3 froze the entire system in 5 minutes.

after that i plugged in an ethernet cable and disabled the airport, I have been watching over 10 HD trailers since then, without a single freeze.
 
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