Try to boot the HD to see if Windows 7 will start. It's likely it won't on different hardware.
Since it's too late to SysPrep to move HD to another computer
the other option is to boot Paragon Adaptive Restore CD
freeware to adjust the OS to the new hardware. It may rarely ask for the SATA controller driver
so be prepared to inject it.
If it won't start after successful adjustment, you may need to boot the Windows 7 installer or Repair CD to run Startup Repair several times.
Once it starts it will change out almost all of the drivers
putting on quite a show you should monitor by clicking the animated driver-loading link from the SystemTray, to watch for several requested reboots.
You may need to install your network adapter to get online, then enable Automatically deliver drivers via Windows Update (Step 3)
and run all rounds of Important and Optional Windows Updates to get newer drivers. After all are completed, check Device Manager for any missing drivers to import from the Device's Support Downloads webpage.