I have a HP Compaq nc6220. Specs are as follows: 40 gb Hard Drive (IDE......ATA-7) 1.7 ghz 1 gb ram Windows XP more info... h18002.www1.hp.com/products/quickspecs/12130_div/12130_div.HTML Are Ultra ATA hard drives compatibility with my laptop? Is there a limit the the size (gb) of hard drive I can upgrade to? Is there a limit to the rmp of hard drive that I can upgrade to? Is there a limited compatibility of hard drive available? Any thing else I need to know when searching buying an internal hard drive? THANKS YOU SO MUCH!!!