Crossfire 5770 Radeon HD High Temperatures

Also, My CPU is the i5-3570K.

I had the same problem in my graphics cards they're the same as yours, after taking them apart I realized there was a layer of thick dust build up around the fins of the heatsink causing massive block of airflow thus heating them, both cards get the problem every year as I live in a dusty house.. Simple solution is to run compressed air through the exhaust of the cards in the back of your computer, do this really good every few months you'll never have a problem.