Hey, I'm working with a HP Pavilion 754n, it has an 80GB HDD in it. I was trying to fix a buddies pc with, so I took out his HDD and connected it in the hp. I tried to boot it, and now the hp's HDD does appear in the bios. I then took a freshly formatted HDD and put windows xp on it. Connected it properly (I checked the connections several times now), and the new HDD does not appear in the bios as well. However, using the same cables, I was able to connect the dvd/cd writer. The dvd drive appears in the bios, but no HDD does. I was wondering if anyone has had this problem and could help me with it. On a side note, the HDD connect through IDE as well as the dvd/cd writer.