I would have the existing one checked out before making a decision.
Does your display show any lights or codes? No would indicate no 12 volt control power.
Yes, it is possible that the control board is bad.
Look in the outside compartment for any debris or yellow substance. present would indicate a failure of the cooling unit. If cooling unit is bad, then a big decision. I personally would go with totally new unit. Replacing a cooling unit and you still have all the other components being old waiting for next item to fail.