Well just when I thought my Windows 10 install was excellent, I ran into another problem - when my PC is off, turning it on results in a restart during the first boot, but the second boot goes through. I haven't had anything like that with Windows 8.1. Hardware-wise my PC was rock-solid with Windows 8.1 - no freezes, crashes, hangs, restarts, etc. Another thing I noticed is that when I boot into desktop, Windows 10 keeps using my HDD - I can hear it spinning (its obvious). I believe it is the reason why right after booting into desktop, Windows 10 is barely responsive for some 30 seconds, during which I can hear my HDD spinning. I have OS installed on primary SSD and there are no startup items or any kind of booting connection to my HDD. In fact, there 0 startup items or 3rd party services or any task scheduled to execute on booting into desktop. HDD is connected via SATA using Intel controller (NOT ASMedia). I have the latest Intel RST drivers installed too. I also can't access my Wi-Fi connection through normal Control Panel - it kicks me out when I double-click on existing Wi-Fi connection. I tried different drivers, but that did not help... I can only connect via global Settings < Network & Internet. Running SFC ScanNow and DISM CheckHealth and Chkdsk with bad sector scan & fix results in no errors/problems being found...
My CPU and GPU are rock-solid, Prime95 for 48hours - no errors. OC is either stable or its not, regardless of the OS. I also can't access my Wi-Fi connection through normal Control Panel - it kicks me out when I double-click on existing Wi-Fi connection. I tried different drivers, but that did not help... I can only connect via global Settings < Network & Internet.