Nothing happens after a black screen appears

I have just changed my PC and when i double click on the unity icon the welcome screen appears and then instead of the sign up screen just a black screen appears and for a long time nothing changes. Before, i thought that it’s gonna work but it’s just not starting nothing happens after the black screen appears, i mean i waited for about 1 hour and nothing changed. Please guys, help me, i am no able to complete my project. I hope because of your help i will continue to make my projects.

Let me mention some details for your convenience

OS : Windows 10 Home 64-Bit
Unity Version : 5.4.2f1

And i have a medium spec PC.

Some people reported that the current beta doesn’t have that problem, so maybe you can try that first.