I just put together a system not long ago, a few months ago. It was crashing running windows 8 with games. I came to realize that those games and windows 8 just didnt get a long.
I did notice that at times, the POST can take up to a few minutes..it shows the logo of the board, asus sabertooth and sometimes it just stick there.
I noticed it locked up on me twice. Hardcore lockup where entire system freezes requiring a hard reboot.