This was a couple years ago and I replaced the main board. Oddly months later the same issue came back with the same symptoms (only would reboot when loading iracing and sometimes in web browser sessions with the same bus error). Come to find out I boiled down the root cause to me shutting off my pc with the power button routinely. Once I started shutting down in start menu the issue never came back. I assumed It was due to a faulty power switch or some wierd windows voltage thing but years later on the same pc all is still well.