Basically what happens is that after booting everything works fine for around 3 minutes on average until the display goes into power saving mode. The only way to exit that is to physically turn off the pc. I tried to just restart the pc and it booted into windows but the screen was still turned off/in power saving mode (windows is the only OS installed so far, im running kali from a live usb.)
So far i tried changing the lock and power options, changing the displays (the same thing happened with another one), i tried using xset and setterm but that didn't work either. The usb works fine on another computer. Im using 2 Ati radeon 6870 HD cards if that helps.
I tried searching the internet and the forums aswell but none of the solutions worked, so any kind of help would be appreciated.
UPDATE:
I tried installing kali linux and i got the same problem, the monitor just goes into powersaving mode and doesn't respond anymore.
Nomodeset doesn't work either.