Thanks for your deep inspection of my trace and detailed answering, cluberti. I have removed Comodo and Malwarebytes software from my OS environment and deleted all System Restore snapshots except the last one. I don't know how to get rid off hard disk pre-delay, there is no direct setting in BIOS (ASUS P8H67 motherboard). I tried to switch SATA controller working mode from IDE to AHCI but I've ended up only with the new fancy Windows 8's BSOD and boot looping. So I switched back to IDE emulation again. Anyway, now the strange thing is happening. While I'm cold booting (powering from "off" state) my PC, Windows 8 starts almost immediately. It takes nearly 5 seconds (maybe even less) after POST to show me logon screen. But if I'm rebooting, the typical lag and the long boot time are still there anyway Here is xbootmgr's long reboot trace: https://dl.dropbox.com/u/406695/boot_trace_20121117.rar I could provide you with the cold boot trace but I don't know what parameter I should use to tell xbootmgr to perform tracing after manual shutdown.