Having the windows 8.1 update issues too.
I am trying to do the update from windows 8 on a pretty much fresh out of the box HP Envy 15.6" Sleekbook with 4th generation i5 core processor, 8GB DDR3, and no dedicated graphics. The only device installed being a Logitec T630 mouse. Other programs are just a few apps from the Windows store, GoPro video editing software, Steam and some Cyberlink programs.
The update get through to checking the drivers and gets maybe half way through (don't think it got over 50% through) before going to a black screen and locking up. The computer then needs to be rebooted by holding the power button until the reboot happens. Then it boots back up and says it is restoring the previous version of windows with the final error message being
"Couldn't update to Windows 8.1.
Sorry, we couldn't update to Windows 8.1. We've restored your previous versions of Windows to this PC. 0xC1900101 - 0x3000D"
It is a shame that Microsoft is so buggy with each release. I find the same thing with my Windows phone which for the most part I love. Apart from the fact that it has now started duplicating every photo I take but you can't even delete just one of the photos.... but that is a whole different rant.