First of all excuse how badly I write english.

I have a question that I have not found a solution for much that I have searched, I am mining in nicehash, two rigs, one of 13 gpus and another of 4 gpus.

I leave you some captures

https://imgur.com/klEugAj

https://imgur.com/rm20ysi

As you can see in the same period of time, the same pool and everything the same, the one with 13 gpus does not exceed 72 shares for any gpu, while the one with 4 gpus gives the least 81 shares.

There is a noticeable difference, why should this be?

Regards!! : )