The old machine is only relevant in relation to the drivers installed on the windows installation. I seriously doubt the old motherboard is driver compatible with the new PC. You need to bite the bullet and simply fork out for a new hard drive, do a windows installation on it, plug in your old hard drive and use it as a slave/storage drive. The only exception to that is if you have your working files stored in a different partition on the old drive from the OS and application files. Either way, you are looking at having to perform a fresh installation of Windows, along with all the applications. If you try doing this on the old drive, make sure you back up EVERYTHING before you start.