At my wits end... IMac shuts down or cannot turn on montior

My IMac randomly shuts down. I have the energy saver set for computer to sleep after 1 hour. I have not installed any new software. This problem began about a month ago. I have to use the restart button and always get an error (posted below), that the computer shut down unexpectedly. I copied one of the Panic Reports if that will help resolve the problem. I have checked the "maximum temperature" in Console and get no messages and many message for "shutdown".
Istat:(Celsius)Temps
HD:MacIntosh 49
CPU 39
CPU Heatsink 39
Fans:
Optical Drive 798rpm
Hard Drive 1599rpm
CPU Drive 1199 rpm
I also use Airport Extreme Version 7.4.2
When I go to reboot, I can feel on the left side of the monitor a vibration. I am assuming that the hard disk is running. I cannot get the monitor to turn on. So I do a reboot and receive the following error message that I do send to Apple.
Mon Aug 2 21:22:21 2010
panic(cpu 0 caller 0x2269f0): "thread_invoke: preemption_level -1, possible cause: unlocking an unlocked mutex or spinlock"@/SourceCache/xnu/xnu-1504.7.4/osfmk/kern/sched_prim.c:1476
Backtrace (CPU 0), Frame : Return Address (4 potential args on stack)
0xf235e8 : 0x21b455 (0x5cf328 0xf2361c 0x2238b1 0x0)
0xf23638 : 0x2269f0 (0x58712c 0xffffffff 0x5870c4 0x2262b4)
0xf236b8 : 0x2270f6 (0x9ce8b98 0x9ce8b98 0xf23718 0x232823)
0xf23728 : 0x227184 (0x0 0x0 0x0 0x291009)
0xf23748 : 0x221948 (0x0 0x0 0x265bf263 0x1)
0xf23768 : 0x4867fc (0x8fc2bc0 0x0 0x91d350c 0x0)
0xf237d8 : 0x486eef (0x0 0x0 0x0 0x8fc2bc0)
0xf23818 : 0x4b1008 (0x91d350c 0x8fc2bc0 0x18 0x5c8710)
0xf23868 : 0x4aef0a (0x91d350c 0x1 0x3998b5c 0x0)
0xf23928 : 0x4c2e1e (0x91d34c8 0xf239c8 0xf23950 0x0)
0xf239e8 : 0xf8e13c (0x40 0xf23a98 0x40 0xf23a98)
0xf23ab8 : 0xf90812 (0x0 0xf95234 0x0 0x0)
0xf23fc8 : 0x29e6cc (0xa4a6990 0x0 0x10 0x9e46a24)
Kernel Extensions in backtrace (with dependencies):
com.apple.nke.asp_tcp(5.0)@0xf89000->0xf96fff
BSD process name corresponding to current thread: kernel_task
Mac OS version:
10F569
Kernel version:
Darwin Kernel Version 10.4.0: Fri Apr 23 18:28:53 PDT 2010; root:xnu-1504.7.4~1/RELEASE_I386
System model name: iMac9,1 (Mac-F2218FC8)
System uptime in nanoseconds: 11066659040716
unloaded kexts:
com.apple.iokit.IOFireWireSBP2 4.0.6 (addr 0xf5e000, size 0x69632) - last unloaded 10919071294029
loaded kexts:
com.cisco.nke.ipsec 2.0.1
com.apple.filesystems.afpfs 9.7 - last loaded 10856663185180
com.apple.nke.asp_tcp 5.0
com.apple.driver.AppleHWSensor 1.9.3d0
com.apple.filesystems.autofs 2.1.0
com.apple.driver.AGPM 100.12.12
com.apple.driver.IOBluetoothSCOAudioDriver 2.3.3f8
com.apple.driver.IOBluetoothA2DPAudioDriver 2.3.3f8
com.apple.driver.AppleMikeyHIDDriver 1.2.0
com.apple.driver.IOBluetoothBNEPDriver 2.3.3f8
com.apple.driver.AppleMikeyDriver 1.8.7f1
com.apple.driver.AppleHDA 1.8.7f1
com.apple.driver.AudioAUUC 1.4
com.apple.driver.AppleUpstreamUserClient 3.3.2
com.apple.DontSteal_Mac_OSX 7.0.0
com.apple.driver.AudioIPCDriver 1.1.2
com.apple.driver.AppleIntelPenrynProfile 17
com.apple.driver.ACPISMCPlatformPlugin 4.1.2b1
com.apple.driver.AppleBacklight 170.0.24
com.apple.driver.AppleLPC 1.4.12
com.apple.GeForce 6.1.6
com.apple.iokit.SCSITaskUserClient 2.6.5
com.apple.driver.AppleIRController 303.8
com.apple.iokit.IOAHCIBlockStorage 1.6.2
com.apple.BootCache 31
com.apple.AppleFSCompression.AppleFSCompressionTypeZlib 1.0.0d1
com.apple.driver.AppleUSBHub 4.0.0
com.apple.driver.AppleFWOHCI 4.7.1
com.apple.driver.AppleAHCIPort 2.1.2
com.apple.driver.AppleUSBOHCI 3.9.6
com.apple.driver.AppleUSBEHCI 4.0.2
com.apple.driver.AirPortBrcm43xx 423.91.27
com.apple.nvenet 2.0.15
com.apple.driver.AppleEFINVRAM 1.3.0
com.apple.driver.AppleRTC 1.3.1
com.apple.driver.AppleHPET 1.5
com.apple.driver.AppleACPIButtons 1.3.2
com.apple.driver.AppleSMBIOS 1.6
com.apple.driver.AppleACPIEC 1.3.2
com.apple.driver.AppleAPIC 1.4
com.apple.driver.AppleIntelCPUPowerManagementClient 105.10.0
com.apple.security.sandbox 0
com.apple.security.quarantine 0
com.apple.nke.applicationfirewall 2.1.11
com.apple.driver.AppleIntelCPUPowerManagement 105.10.0
com.apple.driver.AppleHIDKeyboard 1.2.0a3
com.apple.driver.AppleBluetoothHIDMouse 1.4.0d7
com.apple.driver.AppleHIDMouse 1.4.0d7
com.apple.driver.IOBluetoothHIDDriver 2.3.3f8
com.apple.driver.AppleProfileReadCounterAction 17
com.apple.driver.DspFuncLib 1.8.7f1
com.apple.iokit.IOFireWireIP 2.0.3
com.apple.driver.AppleProfileTimestampAction 10
com.apple.driver.AppleProfileThreadInfoAction 14
com.apple.driver.AppleProfileRegisterStateAction 10
com.apple.driver.AppleProfileKEventAction 10
com.apple.driver.AppleProfileCallstackAction 20
com.apple.driver.AppleSMBusController 1.0.8d0
com.apple.nvidia.nv50hal 6.1.6
com.apple.iokit.IOSurface 74.0
com.apple.iokit.IOBluetoothSerialManager 2.3.3f8
com.apple.iokit.IOSerialFamily 10.0.3
com.apple.iokit.IOAudioFamily 1.7.6fc2
com.apple.kext.OSvKernDSPLib 1.3
com.apple.iokit.AppleProfileFamily 41
com.apple.driver.AppleSMC 3.0.1d2
com.apple.driver.IOPlatformPluginFamily 4.1.2b1
com.apple.driver.AppleSMBusPCI 1.0.8d0
com.apple.driver.AppleHDAController 1.8.7f1
com.apple.iokit.IOHDAFamily 1.8.7f1
com.apple.NVDAResman 6.1.6
com.apple.iokit.IONDRVSupport 2.1
com.apple.iokit.IOGraphicsFamily 2.1
com.apple.driver.BroadcomUSBBluetoothHCIController 2.3.3f8
com.apple.driver.AppleUSBBluetoothHCIController 2.3.3f8
com.apple.iokit.IOBluetoothFamily 2.3.3f8
com.apple.iokit.IOSCSIMultimediaCommandsDevice 2.6.5
com.apple.iokit.IOBDStorageFamily 1.6
com.apple.iokit.IODVDStorageFamily 1.6
com.apple.iokit.IOCDStorageFamily 1.6
com.apple.iokit.IOAHCISerialATAPI 1.2.4
com.apple.iokit.IOUSBHIDDriver 4.0.2
com.apple.driver.AppleUSBMergeNub 4.0.0
com.apple.driver.AppleUSBComposite 3.9.0
com.apple.iokit.IOSCSIArchitectureModelFamily 2.6.5
com.apple.driver.XsanFilter 402.1
com.apple.iokit.IOUSBUserClient 4.0.0
com.apple.iokit.IOFireWireFamily 4.2.6
com.apple.iokit.IOAHCIFamily 2.0.4
com.apple.iokit.IOUSBFamily 4.0.2
com.apple.iokit.IO80211Family 311.1
com.apple.iokit.IONetworkingFamily 1.9
com.apple.driver.NVSMU 2.2.7
com.apple.driver.AppleEFIRuntime 1.3.0
com.apple.iokit.IOHIDFamily 1.6.4
com.apple.iokit.IOSMBusFamily 1.1
com.apple.kext.AppleMatch 1.0.0d1
com.apple.security.TMSafetyNet 6
com.apple.driver.DiskImages 283
com.apple.iokit.IOStorageFamily 1.6.1
com.apple.driver.AppleACPIPlatform 1.3.2
com.apple.iokit.IOPCIFamily 2.6
com.apple.iokit.IOACPIFamily 1.3.0
Any Ideas?
Thank you.

ok then it is back to basic tests if you can go through all the notes we can try and find your connection problems
Here are some help pages done by CL Keith http://www.btinternet.com/~cbeddoe/speed/Speed.html
also post your full hub stats details shown in this link http://www.btinternet.com/~cbeddoe/others/adslstats.html
Can you also post the full results fromBT Speedtest speedtester.bt.com
Have you tried connecting to the test socket at the rear of the master socket
Have you tried the quiet line test? - dial 17070 option 2 - should hear nothing - best done with a corded phone. if cordless phone you may hear a 'dull hum' which is normal
This is a customer to customer self help forum the only BT presence here are the forum moderators
If you want to say thanks for a helpful answer,please click on the Ratings star on the left-hand side If the reply answers your question then please mark as ’Mark as Accepted Solution’

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My iMac has been making a weird noise (fan?) for quite of a while.
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Have you tried resetting PMU? It can also be the PRAM battery is dead/dying.
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Resetting the logic board can resolve many system problems (see
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Message was edited by: spudnuty

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Thanks for visiting Apple Support Communities.
If your iMac shut down unexpectedly, and the fan is running unusually fast or loud, you may need to reset the System Management Controller.
I recommend following this troubleshooting method:
Before Resetting the SMC
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Shut down the computer.
Unplug the computer's power cord.
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http://support.apple.com/kb/HT3964
Best Regards,
Jeremy

At my wits end... IMac shuts down or cannot turn on montior

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