The speed and size of computer chips are limited by how much heat they dissipate. All electronics dissipate heat as a result of the electrons in the current colliding with the device material, a phenomenon called resistive heating. This heating outweighs other smaller thermoelectric effects that can locally cool a device. Computers with silicon chips use fans or flowing water to cool the transistors, a process that consumes much of the energy required to power a device.
Future computer chips made out of graphene – carbon sheets 1 atom thick – could be faster than silicon chips and operate at lower power. However, a thorough understanding of heat generation and distribution in graphene devices has eluded researchers because of the tiny dimensions involved.
I was not sure where to post this, I don't have privilidges to post in the News forums, so I thought this was my next best bet.
This technology is still in development, but it looks promising.