It could be an intermittent fault with the screen (or the graphics card). If re-seating the card and cables doesn't help I would suggest getting in touch with the supplier, particularly as it's still under warranty.
Surface Pro (2017) vs Surface Pro 4
20 groundbreaking 3D animation techniques
How to mine Bitcoin on Mac
Synology invites you to visit them at Insomnia on 26th – 29th August. Book your tickets now and visit Synology.