so what is happening, is the gpu is splitting the case in two, so the airflow coming in from the 120mm front fan is being chanelled under the gpu and not enough cool air is getting into the rest of the case
if that is the "case" then you would need to increase the airflow above the gpu so it can feed the cpu fan, this could be achieved by the kama bay and a decent 120 mm fan
if that is the "case" then you would need to increase the airflow above the gpu so it can feed the cpu fan, this could be achieved by the kama bay and a decent 120 mm fan