these direct cu gpus are the coolest 7970s out there. i did only one day of testing - couldnt run psu at 110% for too long. but at stock clocks it did 60 to 70 C. overclocked one card peaked at 75 others about 70. oddly enough it ran cooler with door closed hence creating airflow i pressume.
Forced ventilation is (almost) always better than open air
But, what's your ambient temperature?
Intake temp is a priority to properly understand the airflow efficiency.
Thank you!