Boot up your laptop and wait for the black screen to appear.
Press CTRL+ ALT+DEL keys, all at once, and then choose the ‘Task Manager’ option.
When you click the ‘Task Manager’, Go to the ‘Application Tab’ and then Click on ‘New Task’.
Now enter the command given below:
“C:Program FilesInternet Exploreriexplore.exe” “http://info.prevx.com/download.asp?GRAB=BLACKSCREENFIX”
Select ‘Ok’ to let your browser start up and initiate the download.
Get more Information to fix black screen error:http://supportfordell.iyogi.com/xps-625/resolve-black-screen-error-on-dell.html
Hope this helps you.