What is the hypothetical hashrate for nVidia GPU doing SHA-256?

[TeamCyr]

I know i know mining Bitcoin with GPUs is dumb idea. But please bare with me, thats not my question.

We are doing an experiment to find out if nVidia cards such as GTX 1070 are even capable of running SHA-256 (for a private blockchain) even if its in the kilo hash its fine, I just need to find the max hashrate. If yes, what is the best miner software I can use? I already have a rig with GTX 1070 that  I can run the test on.

Again this is an experiment that I am working on for someone and I need to let him know what the hashrate is for a GTX 1070.

Thank you for all your help!!