How do you get an A* at CIE A-level?

[ace_uchiha]

Can some1 please explain this to me...because I thought it was the same as the other UK boards, but then some1 was telling me it's a little stricter and that they are set gradethresholds or w/e.
So basically, I'm a bit confused :?:

 

[PlanetMaster]

The course is a little bit tougher than other boards.
But Grade thresholds are for you own good!
GT balances your marks based on difficulty of same paper in past years.

 

[ace_uchiha]

yea i know the course it tougher...it's the board that I'll be doing
and i know gt are for my own good, but i'm wondering if they use this to award your a* (i.e. the number of marks between a grade of A and B will be used to calculate the A*...?) or is it just simply 80% average of the whole a-level course while having an average of 90% in the A2?