TheMatt

Good troubleshooting. You will need a new motherboard. It is pretty simple, you just unscrew the screws holding it to the standoffs and remove it. You should see four screws, one in each of the corners, as well as some in the middle. You will need a philips-head screwdriver to remove the screws which are the same size as those used to hold the hard disk in. Remember, never use a flat-head screwdriver when working with computers.

Once all the screws are out, remove the board by simply lifting it up. Do this in reverse with the new board. You have worked with other hardware before so it sounds like you are experienced in working with computer components.

For the motherboard replacement, you have to consider your budget and the fact that you will likely end up replacing things like the RAM and CPU as well because you are doing an entire platform upgrade.