You could try resetting the BIOS to default. There will be a jumper on the motherboard to do this. Download the manual from MSI if necessary to find the jumper concerned.
If the keyboard concerned is a PS2 type then try a USB keyboard.
Or if the keyboard concerned is a USB keyboard then try a PS2 type.
Try the keyboard with no mouse plugged into the system. If you have added extra PCI cards try removing the extra cards and see if that makes any difference.
Once computer is on try removing the keyboard and then replugging it back in. I have found this to work occasionally on my own computer.
No joy then consider the motherboard to be dead.
