CTO iMac, 3.6Ghz i5, 8Gb RAM random freezes

Hello to you all,

from day 1, October the 13th, my CTO iMac freezes randomly; it has frozen a total of 8 times, 3 of them during the last Apple Keynote, on October the 20th.

When it freezes and there is sound going, it continuously repeats the last sounds, very fast, and the first time this scared me a lot: the first time I thought the loudspeakers broke up (loud scratchy noises, like bangs).
In the other cases, the iMac just freezes, stays there, no heat, no fans going. So here what I've already done:

(1) Contacted Apple, they suggested to (and I did):
(2) Check disk - no problems
(3) Check permission - no problems, solved some inconsistencies
(4) Zap PRAM
(5) Run Hardware Test (I ran the full HW test, all is ok)

And I:

(6) Updated to 10.6.5 and to what System Update was telling me to. (10.6.5 was updated from Combo, as I always do with large system updates)
(7) Checked the temperature of the processor and other temperatures, are all ok
(8) Stressed the iMac with Call Of Duty 4, with the help of a gamer, he played for two hours two times, no freeze.

Until the end of october I had the iMac connected to my router with a Ethernet to power line communication adapter, so thinking that the problem could be related to noise on the power line, I stopped using them and, until today, the problem seemed solved.

Today, after 22 days after the last freeze, I've launched a check of one of my external HD with Sophos Antivirus (I have some Windows files there) and went to lunch. When back, the iMac was frozen, keyboard unresponsive, black screen (should this coming from power save mode).

Details:

(a) iMac i5@3.6 Ghz 8 Gb RAM, all of them same brand (0x80AD)
(b) Bluetooth keyboard and mouse
(c) Time Machine active, the TM HD normally is off, I decide when to make it.
(d) I have the full system.log; there are some errors that I can't explain, but they not always are followed by the freeze.

I've deleted the Chrome App, that was active in some cases; and almost always Safari was running.

I report pieces of my system.log just before the freezes:

(I)

Oct 13 15:07:01 Bugfixer PubSubAgent[298]: SQL Error: SQLITE_CANTOPEN[14.0]: Database file not found
Oct 13 15:09:53 localhost com.apple.launchd[1]: * launchd[1] has started up. *
Oct 13 15:09:57 localhost DirectoryService[15]: Improper shutdown detected

(II)

Oct 15 20:13:03 Bugfixer configd[13]: Hibernate Statistics
Oct 15 20:13:03 Bugfixer configd[13]: Kernel WDDMService com.apple.powermanagement.applicationresponse.cancelled
Oct 15 20:13:13 Bugfixer configd[13]: PMConnection mDNSResponder com.apple.powermanagement.applicationresponse.slowresponse 759 ms
Oct 15 20:13:49 localhost com.apple.launchd[1]: * launchd[1] has started up. *
Oct 15 20:13:53 localhost DirectoryService[15]: Improper shutdown detected

(III, this happened TWO times in a very similar way)

Oct 20 18:53:44 Bugfixer [0x0-0x28028].com.google.Chrome[288]: objc[302]: Class TaskOperation is implemented in both /Applications/Google Chrome.app/Contents/Versions/7.0.517.41/Google Chrome Helper.app/Contents/MacOS/../../../Google Chrome Framework.framework/Google Chrome Framework and /Applications/Google Chrome.app/Contents/Versions/7.0.517.41/Google Chrome Framework.framework/Internet Plug-Ins/PDF.plugin/Contents/MacOS/PDF. One of the two will be used. Which one is undefined.
Oct 20 18:53:44 Bugfixer [0x0-0x28028].com.google.Chrome[288]: objc[302]: Class WorkerPoolObjC is implemented in both /Applications/Google Chrome.app/Contents/Versions/7.0.517.41/Google Chrome Helper.app/Contents/MacOS/../../../Google Chrome Framework.framework/Google Chrome Framework and /Applications/Google Chrome.app/Contents/Versions/7.0.517.41/Google Chrome Framework.framework/Internet Plug-Ins/PDF.plugin/Contents/MacOS/PDF. One of the two will be used. Which one is undefined.
Oct 20 18:54:49 Bugfixer [0x0-0x28028].com.google.Chrome[288]: 2010-10-20 18:54:49.788 Google Chrome Helper[302:207] __CFServiceControllerBeginPBSLoadForLocalizations received error 1100 from bootstrap lookup2
Oct 20 18:58:50 Bugfixer fontd[171]: query/build result time = 0.216912 sec
Oct 20 19:42:14 Bugfixer com.apple.backupd-auto[362]: Not starting scheduled Time Machine backup - time machine destination not resolvable.
Oct 20 19:51:37 localhost com.apple.launchd[1]: * launchd[1] has started up. *
Oct 20 19:51:42 localhost DirectoryService[15]: Improper shutdown detected

(IV)

Oct 20 20:19:47 Bugfixer Nikon Message Center 2[198]: terminate
Oct 20 20:19:47 Bugfixer com.apple.launchd.peruser.501[163] (com.apple.CSConfigDotMacCert-bugfixer@me.com-SharedServices[189]): Exited with exit code: 1
Oct 20 20:20:40 Bugfixer login[217]: USER_PROCESS: 217 ttys000
Oct 20 20:22:30 Bugfixer [0x0-0x17017].com.apple.Safari[223]: FlateDecode: decoding error: incorrect data check.
Oct 20 21:27:18 localhost com.apple.launchd[1]: * launchd[1] has started up. *
Oct 20 21:27:21 localhost DirectoryService[15]: Improper shutdown detected
(V)
Oct 27 19:31:48 Bugfixer apsd-ft[204]: <APSCourier: 0x1022076f0>: Stream error occurred for <APSTCPStream: 0x102103e00>: Error Domain=kCFErrorDomainCFNetwork Code=2 UserInfo=0x10223f400 "The operation couldn’t be completed. (kCFErrorDomainCFNetwork error 2.)"
Oct 27 19:31:49 Bugfixer ntpd[25]: bind() fd 25, family 30, port 123, scope 4, addr fe80::cabc:c8ff:fe89:f4b8, in6is_addrmulticast=0 flags=0x11 fails: Can't assign requested address
Oct 27 19:31:49 Bugfixer ntpd[25]: unable to create socket on en0 (7) for fe80::cabc:c8ff:fe89:f4b8#123
Oct 27 19:31:52 Bugfixer configd[13]: network configuration changed.
Oct 27 19:31:52 Bugfixer configd[13]: Sleep: Success - AC - Software Sleep
Oct 27 19:31:52 Bugfixer configd[13]: Wake: Success - AC - EHC2
Oct 27 19:31:52 Bugfixer configd[13]: Hibernate Statistics
Oct 27 19:32:02 Bugfixer SoftwareUpdateCheck[351]: Checking for updates
Oct 27 19:32:05 Bugfixer apsd-ft[204]: <APSCourier: 0x1022076f0>: Received connected response OK
Oct 27 19:32:08 Bugfixer ntpd[25]: time reset -0.514471 s
Oct 27 19:32:22 Bugfixer loginwindow[35]: no spins reported for this wake
Oct 27 19:32:22 Bugfixer [0x0-0x31031].backupd-helper[343]: Not starting Time Machine backup after wake - failed to resolve alias to backup volume
Oct 27 19:33:59 Bugfixer SoftwareUpdateCheck[351]: SWU: scan found 0 products:
Oct 27 19:33:59 Bugfixer com.apple.launchd[1] (com.apple.suhelperd[352]): Exited with exit code: 2
Oct 27 19:33:59 Bugfixer com.apple.launchd.peruser.501[164] ([0x0-0x33033].SoftwareUpdateCheck[351]): Exited with exit code: 102
Oct 27 19:48:58 Bugfixer com.apple.backupd-auto[369]: Not starting scheduled Time Machine backup - time machine destination not resolvable.
Oct 27 19:52:50 localhost com.apple.launchd[1]: * launchd[1] has started up. *
Oct 27 19:52:56 localhost blued[17]: Apple Bluetooth daemon started
Oct 27 19:52:56 localhost DirectoryService[15]: Improper shutdown detected
(VI)
Oct 29 20:35:23 Bugfixer [0x0-0x6c06c].com.google.Chrome[650]: objc[704]: Class TaskOperation is implemented in both /Applications/Google Chrome.app/Contents/Versions/7.0.517.41/Google Chrome Helper.app/Contents/MacOS/../../../Google Chrome Framework.framework/Google Chrome Framework and /Applications/Google Chrome.app/Contents/Versions/7.0.517.41/Google Chrome Framework.framework/Internet Plug-Ins/PDF.plugin/Contents/MacOS/PDF. One of the two will be used. Which one is undefined.
Oct 29 20:35:23 Bugfixer [0x0-0x6c06c].com.google.Chrome[650]: objc[704]: Class WorkerPoolObjC is implemented in both /Applications/Google Chrome.app/Contents/Versions/7.0.517.41/Google Chrome Helper.app/Contents/MacOS/../../../Google Chrome Framework.framework/Google Chrome Framework and /Applications/Google Chrome.app/Contents/Versions/7.0.517.41/Google Chrome Framework.framework/Internet Plug-Ins/PDF.plugin/Contents/MacOS/PDF. One of the two will be used. Which one is undefined.
Oct 29 20:35:23 Bugfixer [0x0-0x6c06c].com.google.Chrome[650]: [650:24579:7185168778315:ERROR:/b/slave/chrome-official-mac/build/src/net/socke t/clientsocket_poolbase.cc(935)] No pending request for backup job.
Oct 29 20:37:14 localhost com.apple.launchd[1]: * launchd[1] has started up. *
Oct 29 20:37:18 localhost DirectoryService[15]: Improper shutdown detected
(VII)
Nov 21 13:01:27 Bugfixer Safari[523]: Error: Embedded profile header length is greater than data length.
Nov 21 13:01:27 Bugfixer [0x0-0x43043].com.apple.Safari[523]: Sun Nov 21 13:01:27 Bugfixer.local Safari[523] <Error>: Error: Embedded profile header length is greater than data length.
Nov 21 13:01:27 Bugfixer Safari[523]: Error: Embedded profile header length is greater than data length.
Nov 21 13:01:27 Bugfixer [0x0-0x43043].com.apple.Safari[523]: Sun Nov 21 13:01:27 Bugfixer.local Safari[523] <Error>: Error: Embedded profile header length is greater than data length.
Nov 21 13:03:17 Bugfixer SafariSyncClient[535]: LightweightMallornLoginSession is registered.
Nov 21 13:03:17 Bugfixer [0x0-0x46046].com.apple.Safari[532]: 2010-11-21 13:03:17.506 SafariSyncClient[535:903] LightweightMallornLoginSession is registered.
Nov 21 13:06:43 Bugfixer mDNSResponder[26]: Double NAT (external NAT gateway address 10.35.235.89 is also a private RFC 1918 address)
Nov 21 13:37:19 localhost bootlog[39]: BOOT_TIME: 1290343027 0
Nov 21 13:37:08 localhost com.apple.launchd[1]: * launchd[1] has started up. *
Nov 21 13:37:21 localhost fseventsd[31]: event logs in /.fseventsd out of sync with volume. destroying old logs. (9521 14 10864)
Nov 21 13:37:21 localhost fseventsd[31]: log dir: /.fseventsd getting new uuid: ACDF7605-4E75-445B-8081-3DBAA31EE377
Nov 21 13:37:22 localhost DirectoryService[36]: Improper shutdown detected
Thanks for your attention.

iMac 3.6Ghz i5,8Gb - iPhone 3G, iPad, Mac OS X (10.6.5)

Posted on Nov 21, 2010 12:30 PM

Reply
135 replies

Dec 5, 2010 4:11 AM in response to navginrau

Ok,

Summing up:

(1) Not all the i5 users suffer from these freezes (killhippie, would you please so kind to see if you can watch the entire Apple keynote of October, the 20th?)
(2) It can be the RAM, even if tested ok
(3) It can be the internet connection (WiFi or ethernet)

Let's report any other idea or experience. Thanks to all.

Dec 5, 2010 7:07 AM in response to navginrau

navginrau wrote:
Hi Guys.

Kal, I hope your problem is the RAM and simply switch the problem is fixed. But I'm not entirely sure it's only RAM.
In my case my computer was more than a week to repair where the test were also playing music, movies and copying files. During a week !Never frozen!. Why? I think they did not connect my computer to the wifi and maybe this is problem.
Right now I work 3 hours without connecting to the wireless computer (except to write this post) and when not frozen. I will be reporting results at the end of the day.

Bugfixer i want to say freeze, no frostbite. Sorry 🙂


navginrau,

Watching the keynote freezes the iMac systematically. I've a video, too, and I'll show it to the Apple guys.

I've again found in the system.log the usual line:

[0x0-0x81081].com.apple.Safari[914]: FlateDecode: decoding error: incorrect data check.

Later today I'll try to watch it with 4Gb and to boot from an external disk and to see if the Keynote and Safari has the same effect (with 8Gb).

Dec 5, 2010 9:17 AM in response to Bugfixer

What I tried and results:

(1) Booting from an external HD --> Safari + Keynote = Freeze
(2) Booting from internal HD + 4GB RAM instead of 8 --> Safari + Keynote --> NO FREEZE

After (2) I thought that maybe Safari at 32bit could manage to work with 8GB RAM, so I put back the 4GB that I took out the iMac and tried with Safari @32 bit, but it froze again.

So it seems that with 4Gb my iMac works well, at least for what I've seen today.

Dec 5, 2010 11:03 PM in response to killhippie

killhippie wrote:
I have a Mid 2010 21.5" i5 iMac, built in July, it came with 10.6.3 installed and with 8GB ram pre-installed by Apple.

I am sorry you are having such issues That would get to me also, but my iMac has not suffered these issues at all. I connect using WiFi over the 5Ghz spectrum and have not seen your issues. I can watch videos Flash, QT etc with no problems at all and that's with 8GB ram from apple. If there was a massive problem with this configuration there would be a huge number of posts. I imagine, maybe its the Ram or possibly the logicboard, but its certainly not every 21.5" i5 iMac with 8GB Ram. As said mine has not had these issues at all and its been running for 3 months now.


Sorry killhippie,

I had skipped your message, I've read it only this morning. Happy to know that the iMac in this configuration CAN work. Would you please so kind to tell me what is the manufacturer of your RAM chips? You find it on About This Mac/More Info.

My manufacturer (for all the 4 modules) is 0x80AD.

Thanks.

Dec 6, 2010 2:38 AM in response to grueda

Ok, something new, called the support service; so I started my imac pressing shift (for safe mode) (none peripherals attached), the login into accounts/ login items, delete all of them.

Restarted the imac, tried the video on both safari & chrome... it works smoothly... then we clean the memory, restarted the imac cmd alt+pr double bell, and now i'm back, testing...it seems faster, at least is not crashing -yet- so we're waiting...

Dec 6, 2010 2:58 AM in response to grueda

Guys,

I've been on the phone with Apple more than 45 minutes this morning, he could hear the problem by the phone and he pointed me to the closer Apple repair. When I showed the technician the keynote freezing the iMac he said he's never seen a thing like this in many years...

We swapped the back with front modules and the freeze with the keynote occurs within seconds, not minutes.

They will test and call me back as soon as they have an idea...

Grueda,

What you say is quite interesting, what exactly did you delete, the login items that each user has at login time? Do you remember what login items were there?

Dec 6, 2010 3:14 AM in response to grueda

Update: the technician called me a couple of minutes ago; he says that booting from an external Hd WITH A GENERIC Snow Leopard the problem with the keynote Does NOT arise, at least at the moment; this could mean that the OS present on the Mac AND the one on the install DVD are buggy!!!

In fact booting from my external hd with a fresh copy of Snow leopard it froze immediately.

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CTO iMac, 3.6Ghz i5, 8Gb RAM random freezes

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