FUTURE COOLING
Is there a better
way to cool things down than the positively ancient technology of a fan? There have been plenty of ideas. How about using ionic wind? It has no moving parts at all. It works by creating a flow of air using a thin ionizing anode and a large cathode. MIT and NASA have played with the technology as a possible low-emission replacement for jet engines, but so far nothing much has come of it, due to low thrust densities. There have been some lovely homebrew experiments on PCs that appear to work. The main, and absolutely huge, drawback is the massive voltages required—not something you want inside a PC.
Another cooler with no moving parts uses the Peltier or thermoelectric effect. This consists of a sandwich of different materials— typically, carefully arranged p and n-type semiconductors— which has a current passed across it. Heat is transferred from one side to the other as the material tries to find equilibrium among the electrons. It can heat or cool, depending on which way round you place it. It all works well enough, but it’s not the most efficient of systems, the cooling effect isn’t very strong (about 20 degrees difference), and it requires quite a bit of power. The heat isn’t taken very far away either—just across a relatively thin material. On a processor, you would still need something on the other side of your Peltier cooler to carry the heat further away. There is potential, but it has yet to prove itself in anything other than specialist applications. They may be as old as the hills, but fans are cheap and do the job. A good combination.