Yet it premine with hidden gpu miner, get ready ass because it will hurt

there is no gpu miner, also there is no hidden gpu miner!
are you joke? so how do you explain this hashrate?

Maybe it is a botnet or someone rented Amazon EC2.
Doubt it's EC2. Not cost effective. 32 core server was averaging 250H/s. At that rate you'd need to be running 1,200 of those instances to get 300KH/s.
Undoubtedly a botnet or private GPU miner/farm.