This message was posted on behalf of Intel Corporation
Thank you for posting your issue in our community support. In regards to BSOD issues, it would be necessary to narrow down the problem.
The system was working before, so I suggest you to test first the processor. It is better to make the test using the embedded graphics of it (remove external graphics card), use 1 memory stick, uninstall and delete the current Intel® Extreme Tuning Utility application then, install our Intel® Processor Diagnostic Tool and run the stress tool. Let see the results.
Verify if processor base frequency is set to 4.0GHz on BIOS and memories at 2133MHz before running IPDT.
Then, we can start adding the rest of the hardware.
Are you monitoring the Core Voltage in IXTU while you run the stress test? Or the Package and Core Temperatures during the stress test? These items and many others can be displayed if you click the little wrench icon in the upper left hand corner of the graphical and the numeric parameter displays in IXTU.
I doubt this is a CPU problem. Your CPU cooler is adequate, since Skylake processors run cool. No mention of your PC case and case fan configuration, so the internal environment that the CPU cooler works in is unknown.
The rt640rx64.sys driver is a Realtek driver, no doubt part of the audio driver for your board's audio output.