Your rendering device has been lost - Overwatch fix

Set frame rate to capped

Download MSI afterburner - Afterburner - MSI Gaming Series

Set fan speed to manual, as high as you'd like.

Overwatch currently has pretty bad cpu spikes and kicks players in the middle of large fights, even when their system can easily handle the new load. The game thinks it's running at 1k fps, tries to adjust you mid fight and boots.

http://puu.sh/ql03V/c149e07af9.jpg - How my fan setting looks, yours should be similar once it's raised.