I've seen this happen a few times now & think I can manually correct it. I rebooted for a Win10 update, opened the custom fan control section and all the presets are gone. I switched from custom to balanced, then back to custom & my curve was back to normal. Anyone else seen this behaver with the AMD Software? In the past I have started folding after a reboot & had the system crash. I'm guessing the GPU heated to crashing & the fans just never started.