|Your problem is caused by the HPA on the original drive.|
As far as I have seen, ONLY Dell uses a HPA on the original hard drive, and your problem is VERY common with Dell computers.
1710: HPA Makes the Cloned Drive Display Wrong Capacity
You have cloned data from the original drive to a drive with larger capacity. The process completed successfully, but the target drive capacity became the same as the source one, whereas it has to be larger.
The issue is caused by Host Protected Area (HPA) that is on the original drive."
By the way, you CANNOT load a Windows 2000 and up (normal) installation from an external hard drive, because of Microsoft defaults / wishes - you get a blue sceen error message - that's as Microsoft intended.