It is easy to calculate ETHASH power ow Radeon 6800XT , it is close to 2x 5700XT = 103 to 115 MH/s
can you explain pls how you come to this number

It's about as accurate as his/her last post which was guessing ETH would be $9900 at the end of June in 2019. By core count and memory used it looks like it will only be in the 60MH/s. It seems AMD has made significant improvements in efficiency of the architecture so performance per watt in gaming should go up quite a bit. Perhaps it will do the 60 or so MH with the same power draw as the 5700XT which would be about a 20% improvement.
They announced their computer cards today so I expect those to be the real dagger hashimoto winners.