Best way I can explain it. I'm running windows 7. So the computer boots just fine, loads into windows, brings me to the login screen. I hit the log in button, and one of three things happens:
1. Windows loads properly. I can usually tell this when I see my desktop icons refresh and a program on the start bar is running.
2. Windows loads, but the desktop icons don't refresh, and that program on the start bar doesn't load. I can't left or right click anything. Hovering my cursor over the start bar makes it a blue load circle. Ctrl alt del does nothing. Computer is essentially hung, I'm forced to hold the power button in to reset and try again.
3. I hit the log in button, and the computer gets perpetually stuck at "welcome" with the blue loading circle. WIndows never loads, and I'm forced to hold the power button in to reset and try again.
What's weird about this is that it's not consistent. Whether windows loads or not seems completely random. Also, when I do get it to work, windows runs fine all day with no errors.
It might also be worth mentioning that when I boot up the computer, I can't see what's going on until I actually get to the login screen, and then the screen shows up. This happened when I recently changed my primary display driver to a second, newer graphics card, and plugged the HDMI cable into that one instead. This doesn't really bother me...I just hit enter constantly to get past the "start windows normally" menu that I can't see when I have to reset my machine with the power button.