I run an 870, and I get 124s all the time because of my ram. It's been degrading since day one, at first it was 200 pass linx stable at 2000mhz 8-8-8-18 at 1.5v, now it blue screens at 2000mhz 8-8-8-24 1.6v. I replaced the ram with a similar Elpida Hyper kit, and had the same story. CPU is rock stable.

Don't rule out your ram.