How are people hashing that much? Are these generally companies? I can't even imagine an individual with 500+ GPUs
This address is a bit suspect for me, each time visit middlecoins www he have more Mh
I think that only using at least 400-450 units of HD 7990 you can reach that hashing power.
He is for sure working in the factory and each day after work he takes one with him through the backdoor