2 Why do I get a kernel panic 2700 seconds (allegedly) after reboot?
Late 2009 iMac (11,1)
Installed 4x8GB FLEX DDR3, and these seemed to be working fine in OS X Yosemite. No beeping before or after situation described below has hinted at RAM failure.
Two weeks later I replaced original Seagate HD with Seagate ST2000DX001 2TB SSHD. Buggy result after reinstalling from Time Machine (freezing programs, iTunes and AppStore unresponsive), so I decided on a clean install of Yosemite from USB. One kernel panic during installation, but worked fine after reboot.
Everything seemed to be okay, so I tried an upgrade to macOS Sierra from AppStore. Massive fail with chaining kernel panic reboot every 5 minutes or so during upgrade. Installation did eventually complete, but the computer went into repeating kernel panic after a few minutes use - even while just being passively logged in.
According to crash log, the kernel panic always sets in 2700 seconds after reboot (though in reality the panic sets in much earlier). Is this a hint of something specific?
I have tried to
- Nudge RAM modules firmly in place
- Zap NVRAM
- Reset SMC
- Repair, First Aid, Erase HD before Yosemite and/or Sierra installation
- Installed Sierra from USB
I have not yet tried (but will asap)
- Removing RAM modules
- Testing HD in target mode with other Mac
Is this a good question?
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5 Comments
Have you tried booting into Safe Mode? (Restart while holding the Shift key.)
by S W
Booted into Safe Mode in Yosemite. No signs of any panic so far (>50 minutes, more importantly more than 2700 seconds). This is a good sign, no?
by henrikbardum
Finally, after roughly 1hr10minutes...
Fri Jan 6 23:55:58 2017
Panic Report
panic(cpu 6 caller 0xffffff8000416f72): Kernel trap at 0xffffff800010e096, type 14=page fault, registers:
CR0: 0x0000000080010033, CR2: 0xffffff803f5f3000, CR3: 0x000000075bb3b000, CR4: 0x0000000000002660
RAX: 0x0000000003c614dd, RBX: 0xffffff80432537d8, RCX: 0x0000000000000e63, RDX: 0x0000000000008002
RSP: 0xffffff83a338b4e8, RBP: 0xffffff83a338b5c0, RSI: 0xffffff803f5f2fff, RDI: 0xffffff80432544dc
R8: 0x0000000000000001, R9: 0xffffff8000b12f48, R10: 0x0000000000000000, R11: 0x000000007fffffff
R12: 0xffffff83a338b590, R13: 0xffffff8039af6c08, R14: 0x0000000000000000, R15: 0xffffff803f5f2317
RFL: 0x0000000000010206, RIP: 0xffffff800010e096, CS: 0x0000000000000008, SS: 0x0000000000000010
Fault CR2: 0xffffff803f5f3000, Error code: 0x0000000000000000, Fault CPU: 0x6
...
by henrikbardum
Removed two 8gb RAM modules, to immediate negative effect. Machine now in reboot cycle. RAM must be the offender?
These are the ones I'm trying:
https://www.amazon.co.uk/gp/aw/d/B00HET8...
by henrikbardum
@ricky_bartin , ok I just re-read the entire thread. You changed 2 things. a) the RAM, and at first there were no problems. b) then you changed the hard drive to an SSHD.
a) Can you try another hard drive. I've had 2 Seagate SSHDs where the actual hard drive itself is fine. However, the SSD memory was bad. If you say always 2700 seconds into a boot is a kernel panic, it could be the Seagate trying to either move or access data in the SSD part of the hard drive.
b) Try the Seagate SSHD with the known good RAM. Safe mode bypasses all extensions. So some data cannot be read properly either in the hard drive or the RAM, and you know the original RAM was good.
c) If you have fast enough Internet, use the Internet recovery of OS X. https://support.apple.com/en-us/HT201314
by S W