Re: XPS 400 Hard Drive Upgrade
I just upgraded my drive, also, and I ran into a couple of issues - so maybe I can save you some time.
My XPS has two hard drives (250GB x 2) which are configured as RAID. They were formatted to be a system drive C: of 450GB and a recovery drive D: of 50GB (approx). First I tried to replace one of the drives by just changing the cables over to the new drive -- bad idea. These two drives (if you have RAID) need to stay 'coupled'. There are four (4) SATA ports on my mother board. The top are 'primary' and the bottom are 'secondary'. I also discovered that the bottom ports were NOT enabled in the BIOS.
Access the BIOS and enable the lower ports. Then change your BOOT ORDER to use the new drive first, and you can leave the old drive in there with all your data. The old drives will now be D: and E: or similar.
So, here's the short version: Do you have two drives RAID? Don't change the drive config. Go to the BIOS and Enable the secondary/lower SATA ports and then use the BIOS to change your Boot order.
Hope this helps.