Fair enough. There's one more CPU test I'd like you to do. In the active Windows power profile (probably Balanced) please expand the Processor Power Management section and change the maximum AND minimum processor power to be 99% in BOTH cases. This stops the processors entering a low power state when idle. A few CPUs become unstable when transitioning from low power (idle) states to the high-power (running) states. THis workaround will stop the processors entering a low power state.
Let me know whether the BSODs continue after this change.