I was stupid and removed the ram from my windows xp hp pavilion 724c and replaced it with my sister's windows 7 ram thinking that it would make my computer faster. Now when I try to put my windows xp ram back in, it has a long continious beep. The ram is in the slot good., the things clicked and i cleaned the ram using an eraser and my bandana. but it still beeps! PLEASE HELP ME! ;(