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Kernel panic in Yosemite 10.10.3

Problem description:

Kernel panic in Yosemite 10.10.3. 1 or 2 times a day. Not sure if it is software or hardware. I did not have this problem with Mavericks. I require full functionality of Adobe Creative Suite Master Collection (CS6), Logic Pro X, Final Cut Pro X and many other graphic design and sound design apps. Should I backgrade to Mavericks?

EtreCheck version: 2.2 (132)

Report generated 5/2/15, 4:38 PM

Download EtreCheck from http://etresoft.com/etrecheck

Click the [Click for support] links for help with non-Apple products.

Click the [Click for details] links for more information about that line.

Hardware Information: ℹ️

Mac Pro (Early 2009) (Technical Specifications)

Mac Pro - model: MacPro4,1

2 2.26 GHz Quad-Core Intel Xeon CPU: 8-core

17 GB RAM Upgradeable

DIMM 1

4 GB DDR3 ECC 1066 MHz ok

DIMM 2

4 GB DDR3 ECC 1066 MHz ok

DIMM 3

1 GB DDR3 ECC 1066 MHz ok

DIMM 4

1 GB DDR3 ECC 1066 MHz ok

DIMM 5

4 GB DDR3 ECC 1066 MHz ok

DIMM 6

1 GB DDR3 ECC 1066 MHz ok

DIMM 7

1 GB DDR3 ECC 1066 MHz ok

DIMM 8

1 GB DDR3 ECC 1066 MHz ok

Bluetooth: Old - Handoff/Airdrop2 not supported

Video Information: ℹ️

NVIDIA GeForce GTX 680 - VRAM: 2048 MB

DELL P2815Q 1920 x 1080

LCM-22w3 1680 x 1050 @ 60 Hz

System Software: ℹ️

OS X 10.10.3 (14D136) - Time since boot: 1:2:1

Disk Information: ℹ️

HL-DT-ST DVD-RW GH41N

WDC WD3200AAJS-22B4A0 disk0 : (320.07 GB)

EFI (disk0s1) <not mounted> : 210 MB

SchletMacPro (disk0s2) / : 319.21 GB (34.41 GB free)

Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB

Hitachi HDP725032GLA380 disk2 : (320.07 GB)

EFI (disk2s1) <not mounted> : 210 MB

SchletMacProBackup (disk2s2) /Volumes/SchletMacProBackup : 319.08 GB (22.98 GB free)

Recovery HD (disk2s3) <not mounted> [Recovery]: 650 MB

KINGSTON SH103S3240G disk1 : (240.06 GB)

EFI (disk1s1) <not mounted> : 210 MB

KingstonSSD (disk1s2) /Volumes/KingstonSSD : 239.20 GB (27.59 GB free)

Recovery HD (disk1s3) <not mounted> [Recovery]: 650 MB

USB Information: ℹ️

EPSON EPSON Scanner

VIA Labs, Inc. USB2.0 Hub

Sony DRX-840U

Digidesign Inc Mbox USB Audio Device copyright Digidesign 2001

ZOOM Corporation H2 4.04 GB

SCHLETTYH2 (disk4s1) /Volumes/SCHLETTYH2 : 4.04 GB (2.85 GB free)

Seagate Backup+ Desk 3 TB

EFI (disk3s1) <not mounted> : 315 MB

BigRed (disk3s2) /Volumes/BigRed : 3.00 TB (446.51 GB free)

VIA Labs, Inc. USB2.0 Hub

iLok iLok

Apple, Inc. Keyboard Hub

Apple, Inc Apple Keyboard

Apple Inc. BRCM2046 Hub

Apple Inc. Bluetooth USB Host Controller

Configuration files: ℹ️

/etc/sysctl.conf - Exists

/etc/hosts - Count: 5

Gatekeeper: ℹ️

Mac App Store and identified developers

Kernel Extensions: ℹ️

/Library/Application Support/LogMeIn/drivers

[not loaded] com.logmein.driver.LogMeInSoundDriver (1.0.2 - SDK 10.5) [Click for support]

/Library/Application Support/Roxio

[not loaded] com.roxio.TDIXController (2.0) [Click for support]

/Library/Extensions

[loaded] at.obdev.nke.LittleSnitch (4240 - SDK 10.8) [Click for support]

[loaded] com.usb-audio.usb (3.3.0 - SDK 10.8) [Click for support]

/Library/StartupItems/BRESINKx86Monitoring

[not loaded] com.bresink.driver.BRESINKx86Monitoring (6.0) [Click for support]

/System/Library/Extensions

[loaded] com.kernsafe.driver.kscsiprt (1.0.0d1 - SDK 10.9) [Click for support]

[loaded] com.nvidia.CUDA (1.1.0) [Click for support]

[not loaded] com.paceap.kext.pacesupport.master (5.9.1 - SDK 10.6) [Click for support]

/System/Library/Extensions/PACESupportFamily.kext/Contents/PlugIns

[not loaded] com.paceap.kext.pacesupport.leopard (5.9.1 - SDK 10.4) [Click for support]

[not loaded] com.paceap.kext.pacesupport.panther (5.9.1 - SDK 10.-1) [Click for support]

[loaded] com.paceap.kext.pacesupport.snowleopard (5.9.1 - SDK 10.6) [Click for support]

[not loaded] com.paceap.kext.pacesupport.tiger (5.9.1 - SDK 10.4) [Click for support]

Startup Items: ℹ️

Digidesign Mbox 2: Path: /Library/StartupItems/Digidesign Mbox 2

DigidesignLoader: Path: /Library/StartupItems/DigidesignLoader

PACESupport: Path: /Library/StartupItems/PACESupport

Startup items are obsolete in OS X Yosemite

Problem System Launch Daemons: ℹ️

[failed] com.apple.mtrecorder.plist

Launch Agents: ℹ️

[running] at.obdev.LittleSnitchUIAgent.plist [Click for support]

[not loaded] com.adobe.AAM.Updater-1.0.plist [Click for support]

[running] com.eastwest.server.plist [Click for support]

[loaded] com.google.keystone.agent.plist [Click for support]

[running] com.netopia.timbuktu.pro.host.plist [Click for support]

[loaded] com.nvidia.CUDASoftwareUpdate.plist [Click for support]

[loaded] com.oracle.java.Java-Updater.plist [Click for support]

[running] com.synology.SynoSIMBL.plist [Click for support]

[loaded] com.synology.SynoSIMBL_RefreshFinder.plist [Click for support]

[loaded] org.macosforge.xquartz.startx.plist [Click for support]

Launch Daemons: ℹ️

[running] at.obdev.littlesnitchd.plist [Click for support]

[failed] com.adobe.fpsaud.plist [Click for support]

[loaded] com.adobe.SwitchBoard.plist [Click for support]

[failed] com.apple.spirecorder.plist

[loaded] com.avid.sari.plist [Click for support]

[loaded] com.avid.sibelius7.plist [Click for support]

[loaded] com.avid.sibelius75.plist [Click for support]

[not loaded] com.barebones.authd.plist [Click for support]

[not loaded] com.barebones.bbedit.plist [Click for support]

[not loaded] com.barebones.textwrangler.plist [Click for support]

[running] com.bombich.ccchelper.plist [Click for support]

[loaded] com.bresink.system.securityagent3a.plist [Click for support]

[loaded] com.charlessoft.pacifist.helper.plist [Click for support]

[not loaded] com.cocoatech.pathfinder.SMFHelper7.plist [Click for support]

[running] com.digidesign.elevenrack.helper.plist [Click for support]

[running] com.digidesign.fwfamily.helper.plist [Click for support]

[running] com.edb.launchd.postgresql-8.4.plist [Click for support]

[loaded] com.google.keystone.daemon.plist [Click for support]

[not loaded] com.gopro.stereomodestatus.plist [Click for support]

[not loaded] com.logmein.logmeinblanker.plist [Click for support]

[not loaded] com.logmein.logmeinserver.plist [Click for support]

[not loaded] com.MacServe.ivpnHelper.plist [Click for support]

[not loaded] com.makemusic.finale.installer.cleanup.plist [Click for support]

[loaded] com.microsoft.office.licensing.helper.plist [Click for support]

[not loaded] com.noiseindustries.FxFactory.AE.plist [Click for support]

[not loaded] com.noiseindustries.FxFactory.FxPlug.plist [Click for support]

[loaded] com.nvidia.cuda.launcher.plist [Click for support]

[loaded] com.oracle.java.Helper-Tool.plist [Click for support]

[loaded] com.oracle.java.JavaUpdateHelper.plist [Click for support]

[running] com.paceap.eden.licensed.plist [Click for support]

[not loaded] com.quark.quarkupdate.plist [Click for support]

[loaded] com.rogueamoeba.instanton-agent.plist [Click for support]

[loaded] com.skype.skypeinstaller.plist [Click for support]

[not loaded] com.teamviewer.teamviewer_service.plist [Click for support]

[not loaded] com.vmware.launchd.vmware.plist [Click for support]

[not loaded] info.lokiware.attachmenttamer.securetool.plist [Click for support]

[running] org.cindori.TEAuth.plist [Click for support]

[loaded] org.macosforge.xquartz.privileged_startx.plist [Click for support]

[not loaded] org.samba.nmbd.plist [Click for support]

[not loaded] org.samba.smbd.plist [Click for support]

[loaded] PACESupport.plist [Click for support]

User Launch Agents: ℹ️

[loaded] com.adobe.AAM.Updater-1.0.plist [Click for support]

[loaded] com.adobe.ARM.[...].plist [Click for support]

[failed] com.adobe.ARM.[...].plist [Click for support] [Click for details]

[loaded] com.adobe.ARM.[...].plist [Click for support]

[failed] com.akamai.client.plist [Click for support] [Click for details]

[failed] com.akamai.single-user-client.plist [Click for support] [Click for details]

[failed] com.apple.SafariBookmarksSyncer.plist

[failed] com.citrixonline.GoToMeeting.G2MUpdate.plist [Click for support] [Click for details]

[loaded] com.digitalrebellion.SoftwareUpdateAutoCheck.plist [Click for support]

[failed] com.pando.PMB.plist [Click for support] [Click for details]

[running] com.spotify.webhelper.plist [Click for support]

[loaded] com.synology.CloudStation.plist [Click for support]

User Login Items: ℹ️

iTunesHelper Application Hidden (/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)

SwitchResX Daemon Application Hidden (/Library/PreferencePanes/SwitchResX.prefPane/Contents/Resources/SwitchResX Daemon.app)

TrimCheck Application (/Applications/Trim Enabler.app/Contents/Helpers/TrimCheck.app)

CCC User Agent Application (/Applications/Carbon Copy Cloner.app/Contents/Library/LoginItems/CCC User Agent.app)

Internet Plug-ins: ℹ️

o1dbrowserplugin: Version: 5.41.0.0 - SDK 10.8 [Click for support]

JavaPlugin2_NPAPI: Version: 15.0.0 - SDK 10.7

Google Earth Web Plug-in: Version: 7.1 [Click for support]

Default Browser: Version: 600 - SDK 10.10

AdobeExManDetect: Version: AdobeExManDetect 1.1.0.0 - SDK 10.7 [Click for support]

Flip4Mac WMV Plugin: Version: 3.3.1.3 - SDK 10.8 [Click for support]

npSurveillancePlugin_1.0.0.429: Version: SurveillancePlugin_x86_64 1.0.0.429 - SDK 10.6 [Click for support]

FlashPlayer-10.6: Version: 17.0.0.169 - SDK 10.6 [Click for support]

Silverlight: Version: 5.1.30317.0 - SDK 10.6 [Click for support]

Flash Player: Version: 17.0.0.169 - SDK 10.6 [Click for support]

QuickTime Plugin: Version: 7.7.3

googletalkbrowserplugin: Version: 5.41.0.0 - SDK 10.8 [Click for support]

SharePointBrowserPlugin: Version: 14.4.9 - SDK 10.6 [Click for support]

JavaAppletPlugin: Version: Java 8 Update 45 Check version

User internet Plug-ins: ℹ️

CitrixOnlineWebDeploymentPlugin: Version: 1.0.105 [Click for support]

fbplugin_1_0_3: Version: Unknown [Click for support]

WebEx64: Version: 1.0 - SDK 10.6 [Click for support]

Safari Extensions: ℹ️

1Password

Adblock Plus

Open in Internet Explorer

Audio Plug-ins: ℹ️

usb-audio.com: Version: Unknown - SDK 10.8 [Click for support]

Digidesign CoreAudio: Version: 7.4.2 [Click for support]

3rd Party Preference Panes: ℹ️

A Better Finder Preferences [Click for support]

Akamai NetSession Preferences [Click for support]

CUDA Preferences [Click for support]

Digidesign Eleven Rack [Click for support]

DigidesignMbox2 [Click for support]

Digidesign Mbox 2 Pro [Click for support]

Flash Player [Click for support]

Flip4Mac WMV [Click for support]

GoPro [Click for support]

Java [Click for support]

Perian [Click for support]

QuickTime Player X Preferences [Click for support]

SwitchResX [Click for support]

Time Machine: ℹ️

Skip System Files: NO

Mobile backups: OFF

Auto backup: YES

Volumes being backed up:

SchletMacPro: Disk size: 319.21 GB Disk used: 284.80 GB

Destinations:

TimeMachine [Network]

Total size: 11.89 TB

Total number of backups: 61

Oldest backup: 2014-12-04 15:40:46 +0000

Last backup: 2015-05-02 21:13:01 +0000

Size of backup disk: Excellent

Backup size 11.89 TB > (Disk size 319.21 GB X 3)

Top Processes by CPU: ℹ️

6% WindowServer

6% Adobe Illustrator

2% Finder

0% EPSON Scanner

0% Memory Monitor

Top Processes by Memory: ℹ️

1.11 GB kernel_task

609 MB com.apple.WebKit.WebContent(2)

226 MB Dock

191 MB mds_stores

174 MB Safari

Virtual Memory Information: ℹ️

10.00 GB Free RAM

6.68 GB Used RAM

0 B Swap Used

Diagnostics Information: ℹ️

May 2, 2015, 03:35:22 PM /Users/[redacted]/Library/Logs/DiagnosticReports/system_profiler_2015-05-02-153 522_[redacted].crash

May 2, 2015, 03:30:52 PM /Library/Logs/DiagnosticReports/Kernel_2015-05-02-153052_[redacted].panic [Click for details]

May 2, 2015, 03:30:22 PM Self test - passed

May 2, 2015, 05:40:11 AM /Library/Logs/DiagnosticReports/system_profiler_2015-05-02-054011_[redacted].cr ash

May 1, 2015, 07:25:33 PM /Users/[redacted]/Library/Logs/DiagnosticReports/system_profiler_2015-05-01-192 533_[redacted].crash

May 1, 2015, 06:25:27 PM /Users/[redacted]/Library/Logs/DiagnosticReports/system_profiler_2015-05-01-182 527_[redacted].crash

May 1, 2015, 06:18:28 PM /Library/Logs/DiagnosticReports/Kernel_2015-05-01-181828_[redacted].panic [Click for details]

May 1, 2015, 03:25:45 PM /Users/[redacted]/Library/Logs/DiagnosticReports/Mail_2015-05-01-152545_[redact ed].crash

May 1, 2015, 09:51:39 AM /Users/[redacted]/Library/Logs/DiagnosticReports/system_profiler_2015-05-01-095 139_[redacted].crash

May 1, 2015, 07:41:50 AM /Library/Logs/DiagnosticReports/Kernel_2015-05-01-074150_[redacted].panic [Click for details]

May 1, 2015, 07:39:21 AM /Library/Logs/DiagnosticReports/Kernel_2015-05-01-073921_[redacted].panic [Click for details]

May 1, 2015, 12:25:16 AM /Library/Logs/DiagnosticReports/system_profiler_2015-05-01-002516_[redacted].cr ash

May 1, 2015, 12:00:27 AM /Library/Logs/DiagnosticReports/system_profiler_2015-05-01-000027_[redacted].cr ash

Apr 30, 2015, 11:17:47 PM /Library/Logs/DiagnosticReports/mds_stores_2015-04-30-231747_[redacted].cpu_res ource.diag [Click for details]

Apr 30, 2015, 09:09:25 PM /Users/[redacted]/Library/Logs/DiagnosticReports/system_profiler_2015-04-30-210 925_[redacted].crash

Apr 30, 2015, 08:58:54 PM /Library/Logs/DiagnosticReports/Kernel_2015-04-30-205854_[redacted].panic [Click for details]

Apr 30, 2015, 01:46:59 PM /Library/Logs/DiagnosticReports/Preview_2015-04-30-134659_[redacted].hang

Apr 30, 2015, 11:23:09 AM /Users/[redacted]/Library/Logs/DiagnosticReports/system_profiler_2015-04-30-112 309_[redacted].crash

Apr 30, 2015, 11:22:36 AM /Users/[redacted]/Library/Logs/DiagnosticReports/StuffIt Expander_2015-04-30-112236_[redacted].crash

Apr 30, 2015, 11:20:04 AM /Library/Logs/DiagnosticReports/SubmitDiagInfo_2015-04-30-112004_[redacted].cpu _resource.diag [Click for details]

Apr 30, 2015, 10:03:17 AM /Library/Logs/DiagnosticReports/com.apple.photos.VideoConversionService_2015-04 -30-100317_[redacted].cpu_resource.diag [Click for details]

Apr 30, 2015, 09:56:21 AM /Users/[redacted]/Library/Logs/DiagnosticReports/system_profiler_2015-04-30-095 621_[redacted].crash

Apr 30, 2015, 09:55:44 AM /Users/[redacted]/Library/Logs/DiagnosticReports/Photos_2015-04-30-095544_[reda cted].crash

Apr 30, 2015, 09:34:33 AM /Users/[redacted]/Library/Logs/DiagnosticReports/system_profiler_2015-04-30-093 433_[redacted].crash

Apr 30, 2015, 09:34:32 AM /Library/Logs/DiagnosticReports/system_profiler_2015-04-30-093432_[redacted].cr ash

Apr 30, 2015, 09:29:45 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-30-092945_[redacted].panic [Click for details]

Apr 30, 2015, 05:40:11 AM /Library/Logs/DiagnosticReports/system_profiler_2015-04-30-054011_[redacted].cr ash

Apr 30, 2015, 02:16:33 AM /Library/Logs/DiagnosticReports/com.apple.photos.VideoConversionService_2015-04 -30-021633_[redacted].cpu_resource.diag [Click for details]

Apr 29, 2015, 05:56:23 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-29-055623_[redacted].panic [Click for details]

Apr 28, 2015, 05:54:16 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-28-055416_[redacted].panic [Click for details]

Apr 28, 2015, 03:25:26 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-28-032526_[redacted].panic [Click for details]

Apr 27, 2015, 06:02:04 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-27-060204_[redacted].panic [Click for details]

Apr 26, 2015, 11:50:06 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-26-115006_[redacted].panic [Click for details]

Apr 26, 2015, 05:50:49 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-26-055049_[redacted].panic [Click for details]

Apr 26, 2015, 03:33:32 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-26-033332_[redacted].panic [Click for details]

Apr 24, 2015, 05:52:24 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-24-055224_[redacted].panic [Click for details]

Apr 23, 2015, 03:29:36 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-23-032936_[redacted].panic [Click for details]

May 1, 2015, 07:25:27 PM /Users/[redacted]/Library/Logs/DiagnosticReports/Adobe Illustrator_2015-05-01-192527_[redacted].crash

May 1, 2015, 03:25:55 PM /Users/[redacted]/Library/Logs/DiagnosticReports/system_profiler_2015-05-01-152 555_[redacted].crash

Apr 30, 2015, 11:23:05 AM /Users/[redacted]/Library/Logs/DiagnosticReports/StuffIt Expander_2015-04-30-112305_[redacted].crash

Apr 30, 2015, 11:22:47 AM /Users/[redacted]/Library/Logs/DiagnosticReports/system_profiler_2015-04-30-112 247_[redacted].crash

Apr 30, 2015, 09:56:20 AM /Library/Logs/DiagnosticReports/Photos_2015-04-30-095620_[redacted].hang

Apr 26, 2015, 03:31:18 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-26-033118_[redacted].panic [Click for details]

Apr 26, 2015, 03:28:11 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-26-032811_[redacted].panic [Click for details]

Apr 22, 2015, 03:29:30 AM /Library/Logs/DiagnosticReports/Kernel_2015-04-22-032930_[redacted].panic [Click for details]

OS X Yosemite (10.10.3)

Posted on May 2, 2015 2:46 PM

56 replies

May 8, 2015 5:26 PM in response to Richard Schletty

I think you have multiple problems in your Mac. I do not have the breadth of experience with most of the software you are running to advise you what software might be causing some of your issues.

But I want to speak up very strongly on RAM memory errors.

Is it possible that Yosemite is giving false kernel panic reports that point a finger at memory modules?

NO.

Mac Pro error correction is accomplished inside the Xeon Processor Hardware. Eight additional "syndrome" bits (permutations and combinations of parity on various bits in the word) are stored with each word in RAM, and when read back, the processor determines:

• Whether the word read is correct.

• if there was a correctable error (most of these are single-bit errors) which bit(s) need to be fixed, and fixing it.

• whether there was an uncorrectable error (most double-bit errors), which causes a distinctive kernel panic, machine check.

• If a memory error was corrected, leaving an indication that a correction has occurred, so that a background process can tabulate them at its leisure.

If a correctable RAM error is detected, Hardware makes the correction in ONE extended memory cycle -- No interrupts, No subroutines, No OS intervention of any kind. There is no plausible way to have another ordinary problem appear as if it were a RAM Memory problem.

I don't think my three 4 GB sticks magically healed themselves, ...

It would certainly be nice if, once a RAM module developed an issue, it would fall over dead in its tracks. But that is not reality. Memory problems are extremely difficult to isolate, and it may take days of testing and re-testing to finally find out what module(s) fail under what circumstances.

That is why the technique of calling up that report, and going about your business while Hardware checks each and every Read from memory is one good way to proceed.

Your Mac Pro 4,1 has two independent memory subsystems, one assigned to each processor chip. One is made from slots 1, 2, 3, and 4; the other from slots 5, 6, 7, and 8. Whenever you change the number of modules installed on a side (memory subsystem), you also change the timing of accessing all the modules on that side. (example: two modules in slots 1 and 2 are two-way interleaved. Three modules in slots 1, 2, and 3 are three-way interleaved, the fastest access timing. Four modules on a side shares slots 3 and 4, and accessing shared slots is slightly slower overall.)

..., so it has to be software, not hardware.

I disagree.

Different versions of Mac OS X have been known to use RAM Memory in very different ways, and Yosemite uses more RAM Memory and works it harder than any Mac OS X version that came before it. Those machine check panic reports are caused by Hardware -- Flaky Hardware. This can be extremely vexing, but that is what chasing down memory problems is really like.

May 8, 2015 5:59 PM in response to Grant Bennet-Alder

Thanks, Grant. Earlier I wrote: "All I can draw from several assertions here in this discussion is that my memory is BAD for Yosemite 10.10.3 but GOOD for Mavericks." I guess you are saying the same thing, Grant. But now I better understand why. I certainly am learning more about the way memory is utilized differently in Yosemite. I did not know about "memory pressure."

I will continue working with my Mac Pro but will also proceed to do the Apple Hardware Test (now that I have EFI boot after flashing the GTX 680 graphics card) and I'll keep refreshing the status column of System Information: Memory. I would like to get more life out of this Mac. I cannot afford a new silo Mac Pro at this time.

One more thing. Each time I moved modules around in the cabinet, I blew a little more dust out of the fans, corners and crevasses. Who knows – maybe dust was the culprit.

May 9, 2015 6:30 PM in response to Grant Bennet-Alder

Ran AHT. Got this error:

4sns/1/40000000:Tn0D-127.875

A temperature sensor near the heatsink is disconnected or defective. I will either bring to Genius Bar or try to fix myself. Maybe my thermal paste needs replacing, too. My shutdowns were, in fact, similar to RSS with a few MacBook Pros I have rescued with Arctic Silver paste.

May 9, 2015 6:52 PM in response to Richard Schletty

One other possibility, especially since that number (127.875) is near a power of two.

There is a substantial chip, sometimes referred to as the NorthBridge, on the CPU/Memory card. Its heatsink is held in place with two black plastic pins. These rarely break, but when they do, the heatsink on the hottest chip in your Mac Pro is left flapping in the breeze.

Every memory reference passes through that chip. Problems with this usually cause a while raft of kernel panics for unusual and unlikely problems.

May 9, 2015 7:35 PM in response to Grant Bennet-Alder

Thanks for stickng with me, Grant. I had seen info about the broken clip issue and will check it out. The visible black clip at the center of the logic board is intact. I won't be able to inpect the opposite clip until I remove the big heat sink.

I had found this thread: http://forums.macrumors.com/showthread.php?t=1637891

Note that I can only run the short AHT. The extended test freezes at 2 to 3 minutes.

Curiously, Yosemite has had 100% uptime since I did an internet reinstall of 10.10.3 from Recovery utility (about 3 days).

May 9, 2015 8:14 PM in response to Richard Schletty

That trail turns up a thread,

Re: Re: Sensor Error during Apple Service Diagnostics

That contains this picture, posted by tricksters:

May 9, 2015 8:33 PM in response to Grant Bennet-Alder

Yes, I saw that photo (link is in the article I cited). This is exactly what happened. The other spring-loaded pin-clip had broken loose. As soon as I can find the right tool (a long and narrow Phillips screwdriver) to remove the big heat sink over that smaller Northbridge chip sink, I'll be able to devise a way to reattach the small heat sink. I am reading that it's not easy to find a replacement pin-clip. A weak plastic pin combined with a heavy spring was a bad idea, especially as plastic becomes brittle with time and heat. Some have found plastic bolts and nuts to as replacements. Metal is risky as it may short out something on the board.

May 10, 2015 3:28 PM in response to Richard Schletty

some have used nylon nuts and bolts to avoid the possibility of shorten out something. They are commonly available. The downside is one more step (you may have to remove the board) to place the nut or bolt.

It is good you have the expertise to use Thermal Paste, as some of that will be needed as well.

May 10, 2015 11:46 PM in response to Grant Bennet-Alder

Grant, I did the repair using metal bolts and nuts. Nothing shorted out. So far, so good. The short Apple Hardware Test which had reported the sensor/Northbrige problem came up clean. I am now doing extended AHT testing. I'll report back.

Yes, I did appky thermal paste to CPU A, CPU B and the Northbridge chip.

I took photos of the whole procedure and can post these if it would be helpful to others.

I did have a BIG scare, though. The first time I booted the Mac Pro 2009 after repair, the inside of the cabinet lit up with red lights like Santa's sleigh. At that point I thought I had shorted out the logic board but there was no odor or smoke. I took off the CPU heat sinks and inspected the processor modules. Much to my horror, I had bent about two dozen of the very delicate contacts on both CPU mounts. With an X-Acto knife I gingerly bent the leaf contacts back into position, reapplied thermal paste, reattached the heat sinks and said a prayer. It booted!

May 11, 2015 12:15 AM in response to Richard Schletty

May 12, 2015 7:28 PM in response to Richard Schletty

Extended Apple Hardware Test found no errors. My Mac Pro (2009) has been running great for 3 days and nights. I declare a complete cure – no more kernel panics. As you can see from the photos I posted above, I had to cut long bolts to the same length as the plastic pin-clip. I did not know where to buy plastic bolts and nuts. Here are some more photos for your viewing pleasure.

Kernel panic in Yosemite 10.10.3