2009 Early iMac Freezing 3.06GHz,24", ATI 4850

Hi all,

Im frustrated! Went Mac in '94 and haven't had a complaint till now. My new 24 inch iMac with the ATI Radeon HD 4850 freezes too, and on top of that it doesn't connect on the wifi (that's another topic i know). ****...

Hope a solution will come to us shortly...

Apple Insider have picked up the story so maybe Apple will stop declaring they know nothing about it and try to fix it instead.

This is my first mac ever, was expecting much better quality from Apple. Only have it two days, it freezes 6 times already. It's frustrating. First, Apple make us all wait over a month for it, and now it's finally here. It crashes frequently. Apple should resolve this issue soon. Maybe I should request a replacement now before it's too late.

Add another to the list - iMac 3.06, 1Tb, 4850 crashing regularly.

I've reset the SMC, PRAM, reformatted and reinstalled from the supplied disk and sadly none of it worked.

I've done some testing regarding temperature and it doesn't seem to be a factor (according to the iStat Pro at least) though the case does seem to get a little warm to say the least. Could it be faulty temperature sensors (the fans never got near maximum speed despite the case getting uncomfortably warm)?

At one point Safari decided to hang before loading the default home page so I tried Webkit - same result - Safari 4 - Same again - Firefox worked and got me going temporarily. I tried to uninstall Safari 4 and the iMac hung up again, this time completely, refusing to even boot.

After a couple of hours rest I managed to get it to boot again and got Safari working (seems something corrupted the network prefs in a strange way which caused the aforementioned problems).

Guess Apple are getting a call on Monday morning. It's a real pity - I've been a Mac user since the days of the Macintosh Plus (yes I'm that old) and have always been well pleased with the reliability of Macs (apart from the Superdrives which seem to hate me for some reason). And as an X-Plane user I was impressed as **** with the speed that my new iMac was able to run the software even at very high settings.

Oh well...

Setanta

Just thought I'd throw my two cents in here. I have had my new iMac for about a week now. Had the upgraded video card, so it actually took 42 days for delivery. Disappointing when it locks up at least a handful of times per day.

I'm not sure if it's the exact same problem as you guys because it only seems to happen when watching videos. I have been in contact with Apple support and they have assured me that it's an isolated case and they haven't had any other reports of problems with the new iMacs locking up.

Obviously, they must be stumped, just like the rest of us. I was on the phone with support for about an hour and tried to get it to lock up during the call, but was unsuccessful. It did, however, lock up shortly after. The support person walked me through all of the memory resetting and troubleshooting that they and I could think of (that I had already done before) to no avail.

I guess I'll be RSSing this thread and the other similar one while I set up for a refund. It's really too bad because aside from this issue, it's a pretty awesome computer.

Good luck guys.

Message was edited by: jlavoie

Hi,

I've received my 3.06Ghz ATI 4850 24" iMac on Friday and I too have had random freezes. One was during a time machine back-up, another just after coming out of iTunes visualiser and the last was just doing nothing sitting in the Finder.
I've repaired permissions (didn't help) and I've just reset PRAM and we'll see if that helps.
I guess I'll ring Applecare tomorrow

I am also one of the many who have had freezing issues. IDK if this solution will work for everyone but this cured my imac with ATI 4850HD...Mine was over heating because the fans weren't turning on. I installed a a program called "temperature monitor" and viewed how hot my components were (north bridge heat-sink 70c, GPU 60c). I also noticed that every time my GPU would get that hot, my comp would then freeze and I would have to hard reset. I called apple and they mentioned something about a faulty fan. So I thought what the heck, and installed a program called "fan control" (there is a specific version for imacs). Low and behold, the fans weren't responding to apples heat sensor controls and my fans weren't turning on. Fan control took care of this and I now have a perfectly working imac that runs pretty cold without freezes. I hope this helps anyone who has the same issue as me.

Message was edited by: revolvingiris

Got my 3.06 24" yesterday - and after reading about the freezing issue, the devil knocked on my door as well. Frozen once today...

Haven't contacted my local reseller or Apple.

Message was edited by: Hans Pans

I'm actually feeling lucky as of yesterday. After setting up and having some problems out of the gate (three or four locks/freezes in a period of twelve hours, including during long, drawn out Logic content installs), I haven't had a freeze Saturday or so far today.

I even moved 44 gbs of files from one firewire external to a USB drive, which took HOURS, and didn't have any problems. Aside from verifying permissions (there were only a couple off), I haven't done anything (didn't zap PRAM or anything).

Interested in this temperature conversation.

Thought I'd add to the thread... I got my 3.06 GHz ATI 4850 iMac on 4/17, and it has frozen up on me many times since 4/18.

One interesting (though perhaps unrelated) piece of information. If I click "About this Mac", it identifies the CPU as 3.06 GHz. However, if I boot the hardware test and select the hardware tab, it reports 3.60 GHz...

To anyone else experiencing these freezes, what CPU frequency are you seeing in the hardware test? (Hold down the "D" key on boot to check.)

Hi all,
Count me on the random freezing too.
It's happened twice - No rhyme or reason.

Sure hope apple finds a fix soon!

Hi all,

Very interesting topic...
I'm having the exact same model
(3.06GHZ INTEL CORE 2 DUO
4GB 1066MHZ DDR3 SDRAM-2X2GB
ATI RADEON HD 4850 512MB
1.0TB SERIAL ATA DRIVE)
and am also having the exact same lock-up issue.

Just got off the phone with AppleCare and went through al the standard troubleshooting steps already described here and am now geting a new iMac.

One thing I would like to add: installing the Fan Control ( http://www.derman.com/Download/Special/iMacFanControl.html) program, definitly solved the problem.
I'm very curious as to whether this program solves the issue for everyone else. Please try this out and post your results...

Good luck to all!

I just brought my shiny new iMac, same model as above, home about 6 hours ago. I noticed it was running extremely hot, almost burn your hand when you touch it hot, so I installed the temperature monitor app mentioned here. 70C at the Northbridge and GPU heatsink. I installed the Fan Control app and the temps dropped to far more acceptable levels. No crashes, but I think it was only because I noticed the overheating within a few hours and checked here for a remedy.

Can people please share their suggested settings on the Fan Control. I just downloaded it and don't know if I should mess with the default settings or leave them alone.

It's actually very cool to be able to see the running temps of the various locations. Pardon that "cool" pun 😉

i left it on the default values, afraid to do something bad to my machine.
after installation my fans started spinning.

my temps are:

cpu 40 C / 103 F - fan 1660rpm
hd 47 C / 117 F - fan 2405 rpm
GPU 45 C / 113 F



Love to hear from you guys what averages you're seeing

Message was edited by: Hans Pans