I would benchmark the unit and monitor the temps and GPU usage. Then setup a fan profile and adjust the speeds until the GPU is cool enough. Basically turn your fans up on your profile.
They are turend up (the fans) every time they are like on 30%-35%-40%...Depends on what game I play.
But when i press the GAIMING MODE it instantly gets up to 100 celius and the PC automatcly shut's dow. (Sorry for my english )
Is the vidcard fan even spinning when this happens?
If you haven't already done so, I would go into radeon settings/gaming/global setting/global overdrive scroll down and set fanspeed to auto.
I'm sorry, I don't know where this "Gaming Mode" is coming from. I have Gaming/Video/Display... on the bottom of Radeon Settings, but nothing "mode". Are you using the Gaming Evolved app or ? And what does "blocks for 5-10-15..." mean?