BSOD - Critical Process Died...

Yea I know it, in fact, I've got it! I'll run it now and post a screenshot of the results. ;-)

"Here is the memory: It is ALL a matched set of OCZ DDR3 RAM - they came in the same packet, 4x2Gb Modules."
The Intel site shows you should be running 1066 MHz or 1333 MHz, you are using 533MHz.
System Memory for Intel(R) Desktop Board DQ67SW

@jmatt 533MHz is the same as 1066MHz - don't forget it is double data rate (DDR) RAM.

Thanks philc43, missed that. Be interesting to see the results of the 8 pass memory scan.

OK, but slot 0 has a different type of memory to the other slots - this will often cause problems with dual memory channels. I would remove that module and see if the system will boot.

"I'm writing this on the very same system, obviously booted off a spare backup drive with Windows 10 on it, but it runs error free"
Very interesting, if that drive will boot, Lazesoft should.

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@philc43 Right, I removed the module, still got the same error... so it's not hardware...

Thanks for checking - we have to follow the leads and incompatible RAM is a common reason for memory corruption and is a known reason for the 0xEF bugcheck.