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1 iMac stuck during booting from any HD, recovery mode, safe mode, etc.
Hi guys and gals!
I'm having issues with my late 2012 iMac 27" (EMC 2456) with an 3,2 GHz i5 CPU and the GTX 680 2GB.
What doesnt work:
- The iMac does not boot but gets stuck on the gray screen with the apple logo and the horizontal progress bar. The bar stucks at the same position every time.
- It boots neither from the new SSD nor the old SSD, nor any USB device, nor the Recovery Partition, nor into Safe Mode, nor can I install Mac OS through the Internet.
What I tried so far:
- Reseting PRAM/NVRAM (Command-Option-P-R)
- Booting into Safe Mode (holding Shift) doesnt work
- Diagnostic (holding D) works but even the detailed search didnt indicate a hardware fault
- Removed the RAM, restarted and got the alert from the logic board
Kernel Panic Log:
panic(cpu 2 caller 0xffffff7f8f04ed7a): "bool IOAccelDisplayMachine2::display_mode_did_change(uint32_t): vendor driver returns false"@/BuildRoot/Library/Caches/com.apple.xbs/Sources/IOAcceleratorFamily_kexts/IOAcceleratorFamily-378.18.1/Kext2/IOAccelDisplayMachine.cpp:490
Backtrace (CPU 2), Frame : Return Address
Kernel Extensions in backtrace:
com.apple.iokit.IOGraphicsFamily(519.15)[D5F2A20D-CAB0-33B2-91B9-E8755DFC34CB]@0xffffff7f8ec04000->0xffffff7f8ec4cfff
dependency: com.apple.iokit.IOPCIFamily(2.9)[1850E7DA-E707-3027-A3AA-637C80B57219]@0xffffff7f8e894000
com.apple.iokit.IOAcceleratorFamily2(378.18.1)[BAA0383C-9650-3934-B04A-69008F757A2C]@0xffffff7f8f044000->0xffffff7f8f0dafff
dependency: com.apple.driver.AppleMobileFileIntegrity(1.0.5)[54CD88E5-9FD7-30FC-89A0-E4B2D0CE6F85]@0xffffff7f8f013000
dependency: com.apple.iokit.IOSurface(211.12)[E998B85B-3174-3C25-B82B-C0D8BD9720E5]@0xffffff7f8f028000
dependency: com.apple.iokit.IOPCIFamily(2.9)[1850E7DA-E707-3027-A3AA-637C80B57219]@0xffffff7f8e894000
dependency: com.apple.iokit.IOGraphicsFamily(519.15)[D5F2A20D-CAB0-33B2-91B9-E8755DFC34CB]@0xffffff7f8ec04000
com.apple.nvidia.driver.NVDAResman(10.3)[AEA1EB3B-9B42-30F7-B281-208F5ADA51B3]@0xffffff7f8ec75000->0xffffff7f8ef4efff
dependency: com.apple.iokit.IOPCIFamily(2.9)[1850E7DA-E707-3027-A3AA-637C80B57219]@0xffffff7f8e894000
dependency: com.apple.iokit.IONDRVSupport(519.15)[B419F958-11B8-3F7D-A31B-A72166B6E234]@0xffffff7f8ec5a000
dependency: com.apple.iokit.IOGraphicsFamily(519.15)[D5F2A20D-CAB0-33B2-91B9-E8755DFC34CB]@0xffffff7f8ec04000
dependency: com.apple.AppleGraphicsDeviceControl(3.18.48)[89491182-0B41-3BC3-B16F-D5043425D66F]@0xffffff7f8ec6a000
BSD process name corresponding to current thread: WindowServer
Mac OS version:
17E199
Kernel version:
Darwin Kernel Version 17.5.0: Mon Mar 5 22:24:32 PST 2018; root:xnu-4570.51.1~1/RELEASE_X86_64
Kernel UUID: 1B55340B-0B14-3026-8A47-1E139DB63DA3
Kernel slide: 0x000000000de00000
Kernel text base: 0xffffff800e000000
__HIB text base: 0xffffff800df00000
System model name: iMac13,2 (Mac-FC02E91DDD3FA6A4)
What I did prior to the crash:
2 years ago I deleted the fusion drive respectively split it into SSD and standard HD (just mention it in case its relevant for someone)
Yesterday I cut open the iMac and replaced the standard HD with a SSD (Samsung EVO 860 1 TB)
To avoid the fan running to high, I put an Thermostat from OWC (OWCDIDIMacHDD12 Inline-Digital-Thermo-Sensor) between the board and the drive
Did not put in new adhesive stripes yet but fastened the display with duct tape because I first wanted to check whether everything works.
Installed High Sierra through internet on the new SSD.
Whilst performing the migration assistant the monitor turned black.
Reopened the Mac. Disconnected and reconnected the 2 display connectors to the board. The display worked again and I finished installation (this time without the migration assistant).
After about 5 hours of installing, downloading stuff etc. I got a kernel panic.
The iMac then booted neither from the new SSD nor the old SSD, or any USB device. Not even the Recovery Partition.
I opened the Mac and noticed a mellow smell like burned circuit but could not locate that smell. My wife could not smell it so I though I might be wrong.
Next day, I removed the OWC thermostat. The Mac booted again from both disks and seemed to work fine again for a while.
After about 2 hours however I got the kernel panic screen again. I opened the iMac again and I though I smelt something burned again.
Any suggestions on how to proceed would be highly appreciated!
Kind regards
hassscrabbler
(Edited: editorial changes and kernel panic log)
Esta pergunta é pertinente?
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7 comentários
It would be helpful to see what you got for kernel panic errors. Try to see if the system will boot up under Target Disk Mode holding the T key when you restart the system. If you can get it into Target Disk Mode connect via USB or Thunderbolt cable between your system and a second Mac. The iMac's drive should show up as an external drive. If you can't get to it that way you'll need to take the drive out and connect it to the second Mac.
Did you take out the logic board? Or only disconnected the HDD drive cables when swapping out the HDD for the SSD.
por Dan
Hi Dan, thanks a lot for your response.
The kernel panic stated "You need to restart your computer. Hold down the power button until it turns off." in several languages.
The iMac does go into Target Disk Mode. Though I did not try to access it that way, I assume that the SSD is not the issue, as the iMac does not boot from any of the internal nor external (via US) drives.
I did not take out the logic board but only replaced the HDD with the SSD.
Cheers
hassscrabbler
por hassscrabbler
Well, thats good news! So the logic board is OK. Still may have an issue with the drive interface and drive.
If you can connect the second Mac to retrieve the log file as it will have the details on what happened during the startup.
How did you choose which drive to boot up from? Review this useful Apple T/N: Mac startup key combinations. You needed to use the Option key to gain access to the alternate drive. See if that works.
You might want to give the onboard diagnostics a go to see if it pops an error code if it does write it down and post it here for us to see.
por Dan
You talk about the Samsung EVO 960 SSD. Are you sure this what you used? As it's a M.2 blade SSD not a Samsung 860 EVO SATA drive which is what you need.
por Dan
Sorry, my bad! Of course I meant the EVO 860. I had to order a Firewire Cable to read the kernel panic logfile and updated my initial error report (see above).
por hassscrabbler
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