All of the BSODS are indicating a critical process died. It's highly likely this is due to a faulty memory module. You'll want to test your RAM with memtest86 for at least 10 passes or until you hit errors. If you find errors you'll want to shutdown pull all the memory except one module. Retest for 10 passes or until errors. Repeat until you've identified all bad sticks and replace them.
3: kd> !analyze -v
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* *
* Bugcheck Analysis *
* *
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CRITICAL_PROCESS_DIED (ef)
A critical system process died
Arguments:
Arg1: ffffc281f3ca5800, Process object or thread object
Arg2: 0000000000000000, If this is 0, a process died. If this is 1, a thread died.
Arg3: 0000000000000000
Arg4: 0000000000000000
STACK_COMMAND: kb
CHKIMG_EXTENSION: !chkimg -lo 50 -d !nt
fffff80106f1404e - nt!MiPurgeZeroList+6e
[ fa:d7 ]
1 error : !nt (fffff80106f1404e)
MODULE_NAME: memory_corruption
IMAGE_NAME: memory_corruption
FOLLOWUP_NAME: memory_corruption
DEBUG_FLR_IMAGE_TIMESTAMP: 0
MEMORY_CORRUPTOR: ONE_BYTE
FAILURE_BUCKET_ID: MEMORY_CORRUPTION_ONE_BYTE
BUCKET_ID: MEMORY_CORRUPTION_ONE_BYTE
PRIMARY_PROBLEM_CLASS: MEMORY_CORRUPTION_ONE_BYTE