Diagnosing cause of kernel panic on a Mac Pro

I've got an early 2009 Mac Pro with the following specs:

2.66 GHz Quad-Core Intel Xeon

16 GB 1066 MHz DDR3 ECC

NVIDIA GeForce GT 120 512 MB

OS X 10.8.1

Problem is, at random times, my Mac would just shut down and then restart after I clicked through the "gray your Mac shut down without telling you because it's selfish" warning screen.

I took it to a local computer shop and they couldn't really tell, and suggested I do a clean install of Mountain Lion. I did that, got everything back on from Time Machine (just Documents and Music, no Libraries per the technician's instructions), and then last night it did it again. Restarted while I was working on a web site. No notice.

I wondered if someone could help me diagnose the problem or problems(s), since I can't make ANY sense of the sytem report.

Here is the complete system report when the panic occurred. Thanks for ANY help at all you can provide.

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Interval Since Last Panic Report: 228862 sec

Panics Since Last Report: 1

Anonymous UUID: 300EE43F-9F5E-478A-A738-158466678DEC

Fri Sep 7 22:25:11 2012

panic(cpu 2 caller 0xffffff800f2b7b95): Kernel trap at 0xffffff7f90a27975, type 13=general protection, registers:

CR0: 0x0000000080010033, CR2: 0xffffff81fe852000, CR3: 0x0000000011b01000, CR4: 0x0000000000000660

RAX: 0xffffff804da3e400, RBX: 0xffffff804e2ea800, RCX: 0xffffff803113c2c1, RDX: 0x0000000000000000

RSP: 0xffffff81e0f3bd90, RBP: 0xffffff81e0f3bdb0, RSI: 0xffffff8033581b00, RDI: 0xffffff8033581b00

R8: 0x00000000000007bf, R9: 0x0000000000000000, R10: 0x000000000000f784, R11: 0x0000000000000000

R12: 0x0000000000000001, R13: 0xffffff81af85b0b4, R14: 0xffffff81af85b000, R15: 0xffffff804df41800

RFL: 0x0000000000010286, RIP: 0xffffff7f90a27975, CS: 0x0000000000000008, SS: 0x0000000000000010

Fault CR2: 0xffffff81fe852000, Error code: 0x0000000000000000, Fault CPU: 0x2

Backtrace (CPU 2), Frame : Return Address

0xffffff81e0f3ba30 : 0xffffff800f21d5f6

0xffffff81e0f3baa0 : 0xffffff800f2b7b95

0xffffff81e0f3bc70 : 0xffffff800f2ce4ad

0xffffff81e0f3bc90 : 0xffffff7f90a27975

0xffffff81e0f3bdb0 : 0xffffff7f90a276f3

0xffffff81e0f3be00 : 0xffffff7f90a276ab

0xffffff81e0f3be50 : 0xffffff7f90a27936

0xffffff81e0f3be80 : 0xffffff7f90a0c5d2

0xffffff81e0f3bed0 : 0xffffff7f90a0a59f

0xffffff81e0f3bef0 : 0xffffff800f647078

0xffffff81e0f3bf30 : 0xffffff800f645b8a

0xffffff81e0f3bf80 : 0xffffff800f645cb9

0xffffff81e0f3bfb0 : 0xffffff800f2b2677

Kernel Extensions in backtrace:

com.apple.GeForce(8.0)[4B9BE287-5251-398E-96B0-BB16C9BFB2D9]@0xffffff7f90a06000 ->0xffffff7f90ac8fff

dependency: com.apple.NVDAResman(8.0.0)[6A699209-FB98-316B-A3C0-DCA82AA8C86B]@0xffffff7f8f8 d8000

dependency: com.apple.iokit.IONDRVSupport(2.3.4)[99CA4184-8D92-31B2-8726-46139E8E3DFF]@0xff ffff7f8f8c4000

dependency: com.apple.iokit.IOPCIFamily(2.7)[8C9E06A4-13D0-33F5-A377-9E36F0ECC229]@0xffffff 7f8f84d000

dependency: com.apple.iokit.IOGraphicsFamily(2.3.4)[2600903C-EEDE-321B-A023-169DC9B26EA6]@0 xffffff7f8f881000

BSD process name corresponding to current thread: kernel_task

Mac OS version:

12B19

Kernel version:

Darwin Kernel Version 12.1.0: Tue Aug 14 13:29:55 PDT 2012; root:xnu-2050.9.2~1/RELEASE_X86_64

Kernel UUID: 3005059E-270B-3B9F-940D-7A66C05DDC9D

Kernel slide: 0x000000000f000000

Kernel text base: 0xffffff800f200000

System model name: MacPro4,1 (Mac-F221BEC8)

System uptime in nanoseconds: 200816362998684

last loaded kext at 46599045324: com.apple.driver.AppleHWSensor 1.9.5d0 (addr 0xffffff7f91145000, size 36864)

last unloaded kext at 120527452575: com.apple.driver.AppleIntel8254XEthernet 3.1.1b1 (addr 0xffffff7f90492000, size 69632)

loaded kexts:

com.logmein.driver.LogMeInSoundDriver 1.0.0

com.apple.driver.AppleHWSensor 1.9.5d0

com.apple.iokit.IOBluetoothSerialManager 4.0.9f8

com.apple.filesystems.ntfs 3.10

com.apple.filesystems.autofs 3.0

com.apple.driver.AppleTyMCEDriver 1.0.2d2

com.apple.driver.AGPM 100.12.69

com.apple.driver.AppleMikeyHIDDriver 122

com.apple.driver.AppleHDA 2.3.0f2

com.apple.driver.AppleMikeyDriver 2.3.0f2

com.apple.driver.AudioAUUC 1.60

com.apple.driver.AppleUpstreamUserClient 3.5.10

com.apple.driver.AppleMCCSControl 1.0.33

com.apple.iokit.BroadcomBluetoothHCIControllerUSBTransport 4.0.9f8

com.apple.iokit.IOUserEthernet 1.0.0d1

com.apple.driver.AppleLPC 1.6.0

com.apple.GeForce 8.0.0

com.apple.driver.ACPI_SMC_PlatformPlugin 1.0.0

com.apple.Dont_Steal_Mac_OS_X 7.0.0

com.apple.driver.ApplePolicyControl 3.2.6

com.apple.driver.XsanFilter 404

com.apple.iokit.IOAHCIBlockStorage 2.2.1

com.apple.iokit.SCSITaskUserClient 3.5.1

com.apple.AppleFSCompression.AppleFSCompressionTypeDataless 1.0.0d1

com.apple.AppleFSCompression.AppleFSCompressionTypeZlib 1.0.0d1

com.apple.BootCache 34

com.apple.driver.AppleUSBHub 5.1.6

com.apple.driver.AppleFWOHCI 4.9.5

com.apple.driver.AirPort.Brcm4331 601.15.21

com.apple.driver.Intel82574L 2.3.0b4

com.apple.driver.AppleAHCIPort 2.4.0

com.apple.driver.AppleUSBEHCI 5.1.5

com.apple.driver.AppleUSBUHCI 5.1.5

com.apple.driver.AppleEFINVRAM 1.6.1

com.apple.driver.AppleRTC 1.5

com.apple.driver.AppleHPET 1.7

com.apple.driver.AppleACPIButtons 1.6

com.apple.driver.AppleSMBIOS 1.9

com.apple.driver.AppleACPIEC 1.6

com.apple.driver.AppleAPIC 1.6

com.apple.driver.AppleIntelCPUPowerManagementClient 196.0.0

com.apple.nke.applicationfirewall 4.0.39

com.apple.security.quarantine 2

com.apple.driver.AppleIntelCPUPowerManagement 196.0.0

com.apple.iokit.IOSerialFamily 10.0.6

com.apple.kext.triggers 1.0

com.apple.driver.DspFuncLib 2.3.0f2

com.apple.driver.AppleSMBusController 1.0.10d0

com.apple.iokit.AppleBluetoothHCIControllerUSBTransport 4.0.9f8

com.apple.iokit.IOAudioFamily 1.8.9fc9

com.apple.kext.OSvKernDSPLib 1.6

com.apple.iokit.IOSurface 86.0.2

com.apple.driver.AppleSMBusPCI 1.0.10d0

com.apple.iokit.IOBluetoothFamily 4.0.9f8

com.apple.iokit.IOFireWireIP 2.2.5

com.apple.driver.AppleHDAController 2.3.0f2

com.apple.iokit.IOHDAFamily 2.3.0f2

com.apple.nvidia.nv50hal 8.0.0

com.apple.NVDAResman 8.0.0

com.apple.driver.IOPlatformPluginLegacy 1.0.0

com.apple.driver.IOPlatformPluginFamily 5.2.0d16

com.apple.driver.AppleSMC 3.1.3d11

com.apple.driver.AppleGraphicsControl 3.2.6

com.apple.iokit.IONDRVSupport 2.3.4

com.apple.iokit.IOGraphicsFamily 2.3.4

com.apple.driver.AppleUSBHIDKeyboard 165.5

com.apple.driver.AppleHIDKeyboard 165.5

com.apple.iokit.IOUSBHIDDriver 5.0.0

com.apple.driver.AppleUSBMergeNub 5.1.5

com.apple.iokit.IOSCSIBlockCommandsDevice 3.5.1

com.apple.iokit.IOUSBMassStorageClass 3.5.0

com.apple.driver.AppleUSBComposite 5.0.0

com.apple.iokit.IOSCSIMultimediaCommandsDevice 3.5.1

com.apple.iokit.IOBDStorageFamily 1.7

com.apple.iokit.IODVDStorageFamily 1.7.1

com.apple.iokit.IOCDStorageFamily 1.7.1

com.apple.iokit.IOAHCISerialATAPI 2.5.0

com.apple.iokit.IOSCSIArchitectureModelFamily 3.5.1

com.apple.iokit.IOFireWireFamily 4.5.5

com.apple.iokit.IOUSBUserClient 5.0.0

com.apple.iokit.IO80211Family 500.15

com.apple.iokit.IONetworkingFamily 3.0

com.apple.iokit.IOAHCIFamily 2.2.0

com.apple.iokit.IOUSBFamily 5.1.6

com.apple.driver.AppleEFIRuntime 1.6.1

com.apple.iokit.IOHIDFamily 1.8.0

com.apple.iokit.IOSMBusFamily 1.1

com.apple.security.sandbox 220

com.apple.kext.AppleMatch 1.0.0d1

com.apple.security.TMSafetyNet 7

com.apple.driver.DiskImages 344

com.apple.iokit.IOStorageFamily 1.8

com.apple.driver.AppleKeyStore 28.18

com.apple.driver.AppleACPIPlatform 1.6

com.apple.iokit.IOPCIFamily 2.7

com.apple.iokit.IOACPIFamily 1.4

com.apple.kec.corecrypto 1.0

Model: MacPro4,1, BootROM MP41.0081.B07, 4 processors, Quad-Core Intel Xeon, 2.66 GHz, 16 GB, SMC 1.39f5

Graphics: NVIDIA GeForce GT 120, NVIDIA GeForce GT 120, PCIe, 512 MB

Graphics: NVIDIA GeForce GT 120, NVIDIA GeForce GT 120, PCIe, 512 MB

Memory Module: DIMM 1, 4 GB, DDR3 ECC, 1066 MHz, 0x857F, 0x463732353155363446393333334700000000

Memory Module: DIMM 2, 4 GB, DDR3 ECC, 1066 MHz, 0x857F, 0x463732353155363446393333334700000000

Memory Module: DIMM 3, 4 GB, DDR3 ECC, 1066 MHz, 0x857F, 0x463732353155363446393333334700000000

Memory Module: DIMM 4, 4 GB, DDR3 ECC, 1066 MHz, 0x857F, 0x463732353155363446393333334700000000

AirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0x8E), Broadcom BCM43xx 1.0 (5.106.98.81.21)

Bluetooth: Version 4.0.9f8 10405, 2 service, 18 devices, 1 incoming serial ports

Network Service: Wi-Fi, AirPort, en2

PCI Card: NVIDIA GeForce GT 120, sppci_displaycontroller, Slot-1

PCI Card: NVIDIA GeForce GT 120, sppci_displaycontroller, Slot-2

Serial ATA Device: HL-DT-ST DVD-RW GH41N

Serial ATA Device: WDC WD6400AAKS-41H2B0, 640.14 GB

Serial ATA Device: ST31000333AS, 1 TB

USB Device: Keyboard Hub, apple_vendor_id, 0x1006, 0xfa200000 / 2

USB Device: USB Receiver, 0x046d (Logitech Inc.), 0xc526, 0xfa230000 / 4

USB Device: Apple Keyboard, apple_vendor_id, 0x0220, 0xfa220000 / 3

USB Device: LaCie Hard Drive USB, 0x059f (LaCie), 0x1018, 0xfd100000 / 2

USB Device: BRCM2046 Hub, 0x0a5c (Broadcom Corp.), 0x4500, 0x5a100000 / 2

USB Device: Bluetooth USB Host Controller, apple_vendor_id, 0x8215, 0x5a110000 / 3

FireWire Device: built-in_hub, 800mbit_speed

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