The heat sink is a must with the rock pi x. I ordered a fan kit from Amazon that’s originally for the raspberry pi. It came with 4 fans and a ton of heat sinks. I’ve been running a 4K video off YouTube for an hour and she’s holding steady at 1.67ghz. The temp is low on the pi and there’s no thermal throttling. Impressive!

I added a few of the heat sinks to chips that got hot 

Jeremie loves fans. So I put one on it. It really has made a difference to the touch. I’m mostly impressed with the performance. There’s no thermal throttling at all.