Argos, I messed around with the cables and set the harddrives to Master and Slave. I then had some troubles (loooong story), re-installed Windows completely, couldn't see the harddrive... check into Administrative tools and Computer manager (or something.. using Swedish version here) and now... it works.
I can't believe it. I am eternally grateful to you, I can't even describe how you saved me
I now have 19 gigs of extra space and it's all thanks to you. *kisses your feet* Thank you soooo much for the help.