You just have to make sure you get the jumpers correct for the master and slave drives. There is sometimes a picture on the top of the HDD that will tell you the settings for the jumpers so they will register as master and slave. The only thing you might have to do in bios is make sure you have the boot set up for the drive with the os on it. Im pretty sure it automatically boots the master by default. It wont fdisk anything if you dont tell it too. Once you boot to the os you can just drag and drop from one HDD to the next. I did this and it works great if you just want to transfer a few old things. I wouldnt recommend this process though for transferring massive amounts of data, ie 10 gigs.