Ignorable errors 0xc0000017 and 0xc0000018 on boot

Most (but not all) of the time when I boot my desktop system I get a Windows boot error after POST. The error code is 0xc0000017.

When I press enter to "retry" I get error code 0xc0000018. When I press enter a second time I get another error code 0xc0000018. When I press enter a third time the system successfully boots.

I have recorded a video of this behavior for reference here. Please excuse the artifacts induced by interpolating up the frame rate from 10fps to 60fps.

It's not a huge problem because I can get through it by pressing enter three times, but I would like to know what kind of failure could cause these symptoms.

The OS is Windows 8.1 x64 running on a Z87X-UD5H motherboard. Boot drive is an 840 EVO SSD, with the users directory relocated to a separate HD. Additional HDs and SSDs form storage spaces pools for more data. The GPUs are GTX 980s, though I don't think that they are relevant.

Replacing the boot drive, motherboard, CPU, and RAM and doing a clean install of Windows 10 resolved the issue.