The same thing happened to me last night, except I didn't turn my computer off, it went off when the electrity went out in the whole house. This morning,  get the loading screen, then all goes black.  I tried pushing F12 as someone suggested, but its requiring a password to continue. Then, I can't escape from that window. I have to turn it office and start over. Pushing F8 does nothing.

 

last night i logged off the computer ,and powered it off, well couple hours later my wife wanted to use the computer she turned it on and all i got was the dell loading screen and after that the screen goes black and all i have is a blinking curser in the up left corner.What Do i do HELP......

 

I had this happen 2 times on 2 different XPS machines.  I read that it was faulty hard drive, corrupt windows, etc.  Then I read it might just be the video drivers not loading right.  I reboot and on the Dell Splash screen clicked F12 (which brings you to a menu that allows you to select diagnostic mode) enter that and run a test on the video card and the hard drive.  If there are no errors (which was the case in mine) I just exited the diagnostic screen and it worked fine.   Neither machine has had the issue in over a year, so I don't know if it was just an error in loading drivers, or if an update was causing it and now it's fixed.  This might not work for you but before doing anything drastic like replacing parts and reinstalling windows, give it a try.  If it works it's the least invasive thing to do and won't take more than an hour or two.