My old LGE50(ED500) laptop used to run on 2GB(1+1) DDR2 rams of 667Mhz individually.
I tried upgrading to 4gb(2+2) of both 800Mhz speed. But the combination doesn't work. i get horizontal lines on screen at starting of LG logo and freezes there.
I tried with 2gb(800Mhz) in second slot...