Blacks screen with blinking cursor

[Spanky46]

Hello,
Yesterday I bought some new part for my PC:
Asus M4A785TD-V EVO/U3S6
AMD Phenom II X6 1055T
Saphirre HD 5770
Zeppelin DDR3 2x2GB

And the problem is, when I start my PC first time, everything is OK. But after reboot nothing happens. I can see only a black screen with a small flashing cursor in top right corner. It is no possible to go to bios.

Then I must turn the PC off for cca 30 minutes, and then happens the same. After reboot I can see black screen

 

[o1die]

You may need a bios flash with an older am3 cpu, such as the sempron sargas 140. Very few boards will work with the 1055t without a bios flash.