Board Thread:Questions and Answers/@comment-8379598-20130510033217/@comment-8540798-20130510080435

It removes 12 Heat per Second from itself, so you'll need to have a Component Heat Exchanger next to it with your Uranium-/Dual-/Quad-Cell on the other side to maximise it's efficiency

And yes, it's worth using instead of the Overclocked, because the latter can overheat.