My comuter is restarting after putting a new ram?

i setup a new ram with my comp and its a 265.my full system ram is 768(512+256)..after puttin that i can use my comp sumtimes but in most times its restarting b4 windows logon menu..my m.board brand is msi ms7032 iz supporting till 2gb ram....plz help me......(i dont hav a catalogue)