A bug for Pascal seems to have surfaced, while it only effects a very small number of end-users, the impact could be serious if you own a high refreshrate monitor that uses Dual-LinK DVI solely. 

As it stands right now end-users with a founders edition 1070/1080 card (thus not AIB custom cards)  that make use of the dual-link DVI connector could notice problems with booting in-to Windows with pixel clocks set higher at 330 MHz. Now, the circumstances of that happening is slim, VERY slim. The issue was reported on GeForce.com and now is confirmed by multiple end-users. 

So basically users are reporting that if the refresh rate on their (dual-link DVI) monitor exceeds 81 Hz (the highest number achievable while staying under 330 MHz pixel clock), they are unable to boot into windows and the welcome screen is replaced by flashing colors on their monitors. They are unable to boot into Windows until the pixel clock returns to a number under 330 MHz. All this means that dome users with an overclocked Korean monitor (Qnix/Yamakasi) as such could be effected. We assume this could be reproduced on any DL-DVI display that surpasses a 330 MHz pixel clock, but most monitors with a pixel clock of 330 or higher simply use something like Displayport.

If you run into the issue, simply use DisplayPort. If you can't, you'll need to boot into safe mode reset your monitor Hz to a lower value (under 81 Hz) and continue + repeat from there on until Nvidia fixes this (if they can fix it).

GeForce GTX 1070 and 1080 DVI Pixel clock at 330 MHz Issues