that's just a common theme with single fan gaming laptops. I believe the GT version runs a little cooler but still those temps are normal. the CPU and gpu share the same cooling solution so when one gets warm the other raises slightly as well. if you want a cooler running laptop only the Asus g750 can provide that. my gpu temps max w00% gpu around 75c, normally runs around 80% on games at 60-75c.
if yours is the ghost and you do have dual fans, that heating ussue is due to the thinness of the laptop and inability to really push enough air through.
laptops are all about tradeoffs. which when purchasing, you need to look into your options and then decide which one offers the pros and cons your willing to 'deal' with