I recently purchased 4 sticks of faster RAM (DDR2 PC5300 667 as opposed to DDR2 PC4200 533) and put it in. But when I tried to boot, it wouldn't work. One time I got an error message about the frequency being out of range or something weird like that. So I put in my old RAM again and it worked fine. Here is my system: Gateway GT5252 Motherboard: ~Welcome to First International Computer, Inc.~ The motherboard info shows that the RAM I bought should work. I even went to crucial's site (the memory brand's website) and it recommended either the pc4200 or pc5300 for my system. I'm stumped.