Over at twitter a dude with the account name @13a68154676249c posted a photo, and that seems to be the new Radeon 6000 series PCB and blurred GPU. It might be a AMD Radeon RX 6800XT (Navi 21 XT) or RX 6000 (Navi 21 XL). 

The tweet has been deleted, but it likely shows a suspected RX 6000 video card. You can see missing memory ICs and somewhat strange heatsinks on the VRMs, so yes that is an engineering sample. 

The GPU has unfortunately been made hidden, so it is guesswork which chip the card has. According to an attentive commenter on Videocardz, this is a model by Sapphire. There would be a sticker from the manufacturer on one of the ports, and it shows similarities with the RX 5700 XT Nitro + of the same brand. According to rumors, the RX 6900 XT would be an AMD exclusive. So that makes this an RX 6800 or 6800 XT. You can count space for eight gddr6 modules, so its 8 or 16GB 256-bit GDDR6-56 based.

5700 XT Nitro + Special Edition shows not only the shape but also other similarities with the surfaced card.

Is this a Radeon RX 6800XT (Navi 21) engineering board ?