Nothing to do with HDMI. Check airflow in PC case, remove dust and then disable overclocking if enabled. R9 390 is "hot" card by design though.Hey, Just got my Gigabyte R9 390, and I have idle temps at 59-63 celsius with only 1 hdmi connected to a 1080p dell. How come I can't get as low as ypur 39-53 even on single monitor? Is there something wrong with the hdmi on the card?