Hello to everybody!Before a month, my graphics card burned out, and i inserted a new one from my friend.I didn't install the drivers of this card but the drivers of the series of this card.everything was OK.One day, PC restarted without touching it and at windows, a blue screen appeared with a message:RETURN NOT LESS THAN EQUAL.Something like that and other stuff, and it reboot itself.After a few times it did that, i powered off the computer and when i opened it, it started working but i had no signal on the screen.Nothing shows up on the screen.After i reset and turn on the computer a few times, i had signal so i made a backup of my data and continued working, but later the blue screen appeared again and then, after reset, no signal on the screen and i cannot do anything no safe mode nothing, because simply i don't see anything on the screen, while the computer is working. I opened the box and i changed the graphics card with another one.The same result. I put the graphic card on another computer and its working.I tried another screen and i have the same result, although the screen work on another pc.WHAT CAN I DO???