Emptyeye: Assuming you're using Windows, in your %Localappdata%\murphy\Saved\Config\WindowsNoEditor\GameUserSettings.ini file are some options you can switch to turn it on (Why this isn't an in-game option is beyond me; hopefully just an artifact of the game being Early Access) and hopefully take some load off your CPU/GPU:
In the section labeled [/Script/Engine.GameUserSettings]
bUseVSync - Change from False to True
FrameRateLimit - If you want to cap the framerate, change this from 0 to a number you desire
Also, the section labeled [ScalabilityGroups], I'm pretty sure from the variable names that these all relate to graphics quality, and the fact they're all set to 3 corresponds to "high". At least in my case, changing the 3s to 1s at least made the game more stable, though my computer still doesn't have a fun time running it, it does run reasonably smoothly.
(My computer is a ~5-ish year old laptop that, outside of the RAM I've quadrupled between then and now, was pretty middle-of-the-road even when I got it)
Hopefully that helps until they decide to add an in-game menu to change these.
Awesome, my CPU is heated up to just 70°C instead of 95.