So I just installed a new motherboard to accommodate my new CPU (intel i5 6600). However now when I try to connect my GPU (MSI R9 390 8GB) to my monitor by HDMI it doesn't work. I checked to see if the problem lies with the HDMI cable by plugging it into the motherboard's HDMI slot, it worked. Looking inside the PC at the GPU I see the MSI logo glowing, so I know it's getting power, and it is properly installed. I reset the CMOS too. Thank you in advance for your help.