o.k., so i've determined that my intel imac's hd is toast and needs to be replaced. i'm confident that i can change it myself. my only problem is making sure that i purchase the right one as far as compatibility goes. none of the catalogs or websites that sell replacement drives list what computers that the drives are compatible with. anyone know what i need to look for? i'm going to go w/a TB for capacity. thanks to anyone who can help.