Having an interesting problem with my PC and need some help. My system will turn on, all lights, all fans, and all usb devices EXCEPT the screen remains black and there's no mouse or keyboard. Replaced motherboard battery, tried to reinstall RAM, cleaned system unplugged and replugged everything. Tried to see what would happen without GPU in the system and still black screened but the mouse and keyboard turned on (weird). Reinstalled gpu and rebooted: black screen all peripherals on except mouse and keyboard. Tried a different pci slot for the gpu and same thing (black screen all peripherals fine except mouse and keyboard again) What would cause this and is there any fixes ?