T.I.M. Shootout

INTRODUCTION

Advances have been made in many fields of computer technology from displays to video cards and hard drive capacities to thermal pastes. So it shouldn't come as a surprise that no self-respecting enthusiast would ever be caught using generic white paste to help cool their expensive computer equipment. Thermal interface material or TIM is something that anyone with a bit of patience and a few dollars can use to help lower the temperatures of their computer's CPU, video card and even their Northbridge. Back in the day it was perfectly acceptable to use the included white paste that came with heatsinks as the heat output of PC's was much lower than it is today. With ever increasing energy requirements it quickly became apparent that this generic goop just wasn't going to cut it anymore. Company after company began developing the next best thing since sliced bread to help aid in heat transfer. With so many different options available from silver particles to diamond dust it is easy to become overwhelmed in a sea of paste. So let us do the work for you. Come with me as I put some of today's most popular TIMs along with the timeless classics to the test against the white goo to see just how much of a difference it can really make.

The contestants

Thermodynamics 101

Before we begin testing I feel it is important to understand why these materials even exist today. In a perfect world flat would mean just that; flat. Take two flat pieces and push them together for a perfect bond. The problem is that there is no such thing as perfectly flat, only 'flat enough' for whatever your purpose is. Take any heatsink and place it under a microscope and you will see great ridges and valleys that you never knew were there. But that doesn't explain why we need these pastes.

Air is an extremely poor conductor of heat. This has been known for quite some time in the housing industry which is where we get double-paned windows from. In between those two panes of glass is a space of air. When it is cold outside and you have the heat on inside, that space of air helps to keep the cold out and heat in. The inverse of this works in the summer when it is warm outside and you have the AC on inside. With so many ridges and spaces on that 'flat' heatsink of yours there are enough places for air to get trapped that would prevent the transfer of heat from your CPU. This is why we need these pastes. While they do not have the same level of heat conductance as metals used in heatsinks, they are far superior to air. From here they all differ in their chemical composition with some using particles of silver while others use diamond dust for its extremely high conductive properties. Still with me? Good, let's get started.