well if you opened the case already and it was purchased from a dealer or from the net new or refurbished with a waranty,then you have voided it by opening the case,but don`t fret because I happen to have had alot of emachines (sorry to say I still have a few lying around here )lol,anyway they are very aggrevating motherboards,but mine were fine for surfing not for gaming and such,but if you added your other hdd to your system and it didnt work that doesn`t really mean it is bad,I had one that would not do anything on one motherboard but when I installed it in another it worked perfectly,I cannot explain that,because according to specs it should have worked in both,so did you try the bigfoot in the emachine?I would and some of those emachines for some reason require you to just go into setup and leave lol in order for the hdd to be recognized weird I know but they are their own breed lol,and as far as the other hdd not recognized in your pc I have also run into that,it seems that all hdd`s don`t work as you had them on 1 ide cable well only in certain setups that is,and I don`t think it would hurt if you just hooked up the one out of the other pc into yours alone to see if it will post.