Guys! I know how to fix this problem, just made it by myself. (first of all, sorry for my sucky english..). Ok so what I did was:
Updated my BIOS to the newest version.
After that I removed my old card's drivers.
Installed the new card <- and here comes the important thing. Everyone is thinking that when you hear this "click!" sound that comes out of MOBO when you press your graphics card in, is good, but not this time. R9 card's are fu**ed up. You have to press them very very hard in, and you have to do the same progress with all cabels connected to the graphics card. After you heard the "click!" sound, don't stop but dont break the mobo..
(Btw. when you press the card in, you should hold your case with one of your hand on the...