I have a compaq with a SATA HDD C: drive, a DVD rom also on SATA, and a 2nd HDD on PATA. I bought a 2TB WD SATA HDD to replace the HDD I had on PATA. I only have 2 SATA spots in my computer so I removed the DVD drive and connected the new SATA HDD I bought and removed the PATA HDD. My computer lists the new drive but I cannot format the new drive. On quick format, it says windows cannot format the drive, check the connections which I did. On normal format mode, the format takes about 3 hours and gets stuck just past 50% and stays like that forever. I have VISTA and it did not come with a CD, the OS was preloaded onto my computer. Can someone please help?