I just bought DDr2 2gb ram 800mhz... and when i insert the ram in my computer, my system becomes very slow.. i already have a ddr2 2gb ram and my system has intel(R) Core(TM)2 Duo CPU, E6550 @2.33Ghz.. Windows XP, Version 2002, service pack 3. so my question is Is DDr2 800Mhz is the proper one or what kind of ram should i buy?