So, I managed to dual boot Windows 8.1 and Ubuntu 13.04. In Ubuntu 13.04, I installed the drivers for my graphics card(AMD HD Radeon 7700 Series, I'm pretty sure it's a 7790 one and Intel HD Graphics 4600 for Motherboard, but this shouldn't be necessary, considering that it's not the motherboard where I have connected the HDMI) for HDMI. I went to System Settings, and then to Sound, selected the HDMI sound option. Now, whenever I play anything that has sound, the audio has static and crackling. It does not play correctly. I tried searching, but all I find is questions in which the HDMI audio is simply not recognized and not playing.