My Dell Optiplex 390 won't go pass the startup screen. It keeps telling me to restart my computer or advanced options?? I have no clue what to do?? Could someone plz help me?? I know a lot of people are going to think I'm stupid, because this is probably a simple or obvious fix but I don't know how to fix this issue. I have tried Google and YouTube for help and this website is the most helpful thing I've found.