After installing new AMD driver, monitor gets no signal

[AI_controller]

Hello all,

This is my second day using my first computer that I built from scratch. There has been a lot of issues that arose, but thankfully nothing too serious that I could not find a fix. This latest one though, I have absolutely no idea, and frankly, am quite scared. The drivers for my graphics card, a r7 260x, asked to be updated and installed a new AMD software on my computer. After installation, I decided to wait and do more computer work before I rebooted the computer for the setting to take place. When I finally got around to it, I rebooted a and then left the room. I have no idea what happened during the reboot because when I came back the computer was turned off rather than rebooted, and now no matter what I do be it connecting the DVI cable to the motherboard rather than the graphics card, or trying a different monitor, nothing seems to work nor fix it the no signal message on the monitor. It is a purely black screen. Also, another weird thing that never happened prior to the driver install is sometimes when I press the power button on the PC it starts for a while then turns itself off. Please if you have any idea at all, I will greatly appreciate it.