To be precise, download iTunes to your new computer. Get iTunes set up and choose not to sync when your iPad is connected. Then connect your old iPad, and do a backup. Then connect your new iPad and rather than set it up as a new iPad, choose restore from a backup and restore from your old iPad backup. If this isn't clear Google it. There are several step-by-step outlines for doing what you want. The first step is to backup your old iPad once iTunes is installed on your new pc.
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