Probably something that everyone knows but me!!!! Will a wallstreet cpu [w/cache] plug and go into a mainstreet? Is there a place where one can find what fits what?? I have a really nice [physically] mainstreet powerbook, cause it aint fast it hasn't had much use....Maybe a small inexpensive "upgrade" will give it a more useful life... Thanks in advance for your kind assistance, and patience with "we the unknowing"!!