Unplug the new drive and see if it boots with windows XP'
Did you, before even installing Windows 7 on the new drive, connect the drive and use Windows XP to set the Partion to Active, and make a Boot/Primary Partion and reformat this drive to NTFS???? if you didn't, this is the first thing that is wrong, then did you select the Drive and format it with the Quick format During the windows 7 install?
Have a look at this: Link Removed - Invalid URL
Do how they have done it, But set up the new drive first.
I'am guesing that the new drive is SATA, what is the old drive, SATA or one of those IDE ones that use that fat, wide Ribbon cables.