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

Hi all.

First mac for me so I'm probably missing out on obvious steps.

Similar to the issues other people are having, my computer is freezing up. What no other thread seems to mention is whether their macs freeze exclusively in OSX or in Windows as well (under bootcamp).

In my case its freezing under both and it doesn't happen in any particular moment. It can happen whilst playing a game or simply leaving the computer on at night.

I've tried the following tests:

· Apple hardware test - All ok
· Rember (GUI for Memtest) - All ok
· Repair disk permissions - There were many errors but fixing them didn't do anything

I have yet to try the "SMC reset" if I knew how to... anyone?

Remaining things to try:

· SMC reset
· PRam reset
· Reinstall OS (which option do i choose? Erase or not erase?)

· Phone Apple - I imagine they will keep me in hold forever and ask me to do a zillion tests so I want to try out all the tests I can so that the call doesn't become one of many.

iMac 24" 3.06Ghz ATI 4850 HD (Early 2009), Mac OS X (10.5.6)

Posted on Apr 16, 2009 6:55 AM

Best reply

rkaufmann87

Level 10

140,922 points

Posted on Apr 16, 2009 7:02 AM

Below are instructions on how to do SMC and PRAM reset together:

1. Turn off your iMac and unplug everything from it for 30 seconds.

2. Plug in the power cord, keyboard and mouse only.

3. Press the power button and immediately hold down the Option, Command, P & R keys until you hear the second gong then release the keys. Your machine will start up normally, then check for the issues you are having.

View in context

224 replies

Jim Kohn

Level 1

50 points

May 2, 2009 12:31 PM in response to tthiel1

Funny you should ask: FedEx just came down the driveway and I'm about to install the 8GB kit they brought me. Do I really think it's going to make a significant difference over 4GB? Not so much. Truth be told I really just like having top spec Macs. Call it a guilty pleasure. Cheers.

May 2, 2009 1:27 PM in response to Jim Kohn

Yay! Agreed, that didn't take long at all. I am very relieved. I'll give it a go this weekend.

dadj77

Level 1

14 points

May 3, 2009 12:49 PM in response to Community User

So, how is this update working for you guys & gals? I just installed it myself but my iMac with the ati 4850 did never freeze anyway (didn't use wifi anyway if that was the cause..)
At work i use a year old iMac which has freezing issues though. All updates are installed on it but freezes remain. so i guess for that series the update did not (always) work..

May 3, 2009 3:53 PM in response to dadj77

Seems to be holding up well. I haven't had wifi on long yet, but no freezing so far. I will update for the next few days.

May 4, 2009 10:05 AM in response to Justice Jr

Hi
I got my first (ever) iMac in April '09 with wireless mouse.
It started freezing on me about 2 or 3 weeks after I got it. I've always thought that it is battery's fault, so I would restart "frozen" iMac and change the batteries. I know....:-)
But now, it happens even when I have new batteries in my mouse.
I read through this thread and it seems that this problem occurs mostly in iMacs with Radeon card. I have NVIDIA GeForce GT 120 256MB, can I still download this EFI Firmware Update 1.4 ? Or should I do something else?
Thanks for help !!!

May 4, 2009 10:13 AM in response to Bambaryla

Apple has released an EFI update that addresses the freezing issues you've been having. You can download it through Software Update (accessible from the Apple menu) or go to this website:

http://support.apple.com/downloads/iMac_EFI_Firmware_Update_14

May 4, 2009 3:45 PM in response to Community User

The firmware update seemed to fix the issues I was having. I'm going to try re-enabling the WiFi on the Windows side to see if I still get issues there.

A couple of things for the Mac-savvy out there. I downloaded Fan Control which seems to do a good job of keeping things cool during Leopard operations, but when I boot into my Vista partition, the computer gets a little toasty. Is there a recommended version for Windows of the Fan Control app that can cool things off?

Secondly, I'm having a "low USB Hub power" warning show up in Vista when plugging in the iPhone. Has anyone seen this, and know of a fix?

May 4, 2009 4:51 PM in response to Justice Jr

The latest firmware seems to be working great. Not a single lock up since installation. I think this is it. Thanks Apple tech support/engineers.

May 5, 2009 8:55 AM in response to Community User

great to see the prblems been fixed, great news!!!!!!

May 5, 2009 9:01 AM in response to Community User

great to see its been fixed, great news !!

May 5, 2009 2:36 PM in response to Jack.wilson16

After two days of no freezes, it has resurfaced after install of Firmware update. Back to square one.

May 5, 2009 2:40 PM in response to Aquapaddler

Sorry to hear, Aquapaddler. Please post any resolution.

McJPP

Level 1

0 points

May 5, 2009 5:44 PM in response to Aquapaddler

Sorry to hear that. I too seem to be having a similar issue after applying the firmware fix.

Exact same kind of freezing but not while playing online videos as before AND not nearly as often.

Can't figure what is causing the freeze but it has similar characteristics - i.e. mouse and keyboard stop working completely. I can see the cursors but the machine doesn't respond to keystrokes or mouse clicks. Both keyboard/mouse are wireless, btw. Oh yeah...i'm also using a dual monitor setup with my Cinema display.

The only way out of it is a hard reboot.

I'm going to monitor this after running Cocktail but i'm afraid that the fix hasn't been perfect for me (yet).

Interesting to hear if anyone else is having similar problems.

...john...

UPDATE: So sorry i added this before checking other threads. It appears this may be related to some bluetooth issues many are experiencing that should be fixed in the 10.5.7 update.

Message was edited by: McJPP

May 5, 2009 6:18 PM in response to McJPP

Additionally, I have found Mighty Mouse issues when connecting my new iMac to a second monitor. I am using a Miniport to DVI to Viewsonic VA1912wb. The mouse was intermittent or "jumpy" when moving across the screen. I thought this was a Bluetooth issue; however, when I disconnected my second monitor, my wireless mouse performed as expected.

May 6, 2009 3:26 PM in response to Aquapaddler

Something new developed today - a red vertical line from the top of my screen to the bottom. I have very patient but I have reached my limit. Machine is going back. I don't want a replacement at this point.

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