system
A chat on subreddit /r/pcmasterrace
human
It is. And you can. But unless you're having issues, you probably shouldn't need to, unless it came with a cooler you've removed.
gpt
There was no cooler. The PC was meant to be a Workstation. I use it as a Home-Server with 6 HDD/SSD and 5 network interfaces. With every additional drive/network card the Chipset (Skylake) temp rises. Now I got 68C and it‘s running 24/7. 
If a passive heatsink (like the Raspi ones) can bring the temp down to 55-60C I would be satisfied. ;-)