Motherboard has a long beep after initialization

Did you try with different RAM module? If yes and still having the problem then its the keyboard connector which is having problem. Most of the time the capacitors next to the connector, which are meant to subside the external noise, do not function properly. If you have soldering iron, just get rid of those capacitors and you are good to go. If all fails then south bridge has problem which can not fixed easily(in most cases it can't be fixed). Hope this helps.