You say just updated but are all the start/end dates the same and the three numbers on the strip on the back the same? If anything is changed you will need to update the details on Paypal. I had to change my details when Santander sent me a replacement for my Abbey card as they'd changed the expiry date and the number on the back strip.
I don't think you could purchase through Paypal if they don't have the full details of your card.
If your new card details are identical why did they send you a new card unless you've only changed the picture?