On that motherboard you can upgrade to 8GB and a 2.1ghz quad core AMD (older version). To use the 8GB you will need a 64 bit OS (Windows 7).
Did you say AMD processor on Intel system? Oh no, Come on. AMD processor dosnt supprot intel based system. They both use different socket and different technology. AMD processor needs only amd supported motherboard and intel processor needs intel proccessor supported motherboard.